How to create an array of n rows and 5 columns in C++, but the n value is changing
2
I've this code, where I want to create a dynamic 2-d array with n x 5 values -
int** bump = new int*[b_bump_num];
for(int i = 0; i < b_bump_num; i++) {
bump[i] = new int[5];
}
for(int i = 0; i < b_bump_num; i++) {
delete bump[i];
}
delete bump;
But I'm facing this error -
*error:Expressions must contain pointer types-The third last line-bump[i]
c++ arrays
asked Nov 20 '18 at 6:49
doudou
134
|
show 4 more comments
2
I've this code, where I want to create a dynamic 2-d array with n x 5 values -
int** bump = new int*[b_bump_num];
for(int i = 0; i < b_bump_num; i++) {
bump[i] = new int[5];
}
for(int i = 0; i < b_bump_num; i++) {
delete bump[i];
}
delete bump;
But I'm facing this error -
*error:Expressions must contain pointer types-The third last line-bump[i]
c++ arrays
asked Nov 20 '18 at 6:49
doudou
134
which compiler are you using? Nothing wrong with your code. Please post the exact error message and a Minimal, Complete, and Verifiable example
– Alan Birtles
Nov 20 '18 at 7:53
I am very sorry, I use this software for the first time, many things do not understand, thank you for explaining to me
– dou
Nov 20 '18 at 7:54
An error is reported on the The third last line line: the expression must contain pointer type
– dou
Nov 20 '18 at 7:56
3
@dou Unrelated: In C++ you have a better option. Its calledstd::vector<>. And as usual, the question would be; is there any special reason that you are not using it?
– JeJo
Nov 20 '18 at 8:01
@JeJo:Can you give me an example of code usage?I do not have the programming foundation, a lot of basic knowledge do not understand, can only learn from the program example
– dou
Nov 20 '18 at 8:11
|
show 4 more comments
2
2
2
I've this code, where I want to create a dynamic 2-d array with n x 5 values -
int** bump = new int*[b_bump_num];
for(int i = 0; i < b_bump_num; i++) {
bump[i] = new int[5];
}
for(int i = 0; i < b_bump_num; i++) {
delete bump[i];
}
delete bump;
But I'm facing this error -
*error:Expressions must contain pointer types-The third last line-bump[i]
c++ arrays
asked Nov 20 '18 at 6:49
doudou
134
I've this code, where I want to create a dynamic 2-d array with n x 5 values -
int** bump = new int*[b_bump_num];
for(int i = 0; i < b_bump_num; i++) {
bump[i] = new int[5];
}
for(int i = 0; i < b_bump_num; i++) {
delete bump[i];
}
delete bump;
But I'm facing this error -
*error:Expressions must contain pointer types-The third last line-bump[i]
c++ arrays
c++ arrays
asked Nov 20 '18 at 6:49
doudou
134
asked Nov 20 '18 at 6:49
doudou
134
edited Nov 20 '18 at 8:00
dou
asked Nov 20 '18 at 6:49
doudou
134
asked Nov 20 '18 at 6:49
doudou
134
asked Nov 20 '18 at 6:49
doudou
134
134
which compiler are you using? Nothing wrong with your code. Please post the exact error message and a Minimal, Complete, and Verifiable example
– Alan Birtles
Nov 20 '18 at 7:53
I am very sorry, I use this software for the first time, many things do not understand, thank you for explaining to me
– dou
Nov 20 '18 at 7:54
An error is reported on the The third last line line: the expression must contain pointer type
– dou
Nov 20 '18 at 7:56
3
@dou Unrelated: In C++ you have a better option. Its calledstd::vector<>. And as usual, the question would be; is there any special reason that you are not using it?
– JeJo
Nov 20 '18 at 8:01
@JeJo:Can you give me an example of code usage?I do not have the programming foundation, a lot of basic knowledge do not understand, can only learn from the program example
– dou
Nov 20 '18 at 8:11
|
show 4 more comments
which compiler are you using? Nothing wrong with your code. Please post the exact error message and a Minimal, Complete, and Verifiable example
– Alan Birtles
Nov 20 '18 at 7:53
I am very sorry, I use this software for the first time, many things do not understand, thank you for explaining to me
– dou
Nov 20 '18 at 7:54
An error is reported on the The third last line line: the expression must contain pointer type
– dou
Nov 20 '18 at 7:56
3
@dou Unrelated: In C++ you have a better option. Its calledstd::vector<>. And as usual, the question would be; is there any special reason that you are not using it?
– JeJo
Nov 20 '18 at 8:01
@JeJo:Can you give me an example of code usage?I do not have the programming foundation, a lot of basic knowledge do not understand, can only learn from the program example
– dou
Nov 20 '18 at 8:11
which compiler are you using? Nothing wrong with your code. Please post the exact error message and a Minimal, Complete, and Verifiable example
– Alan Birtles
Nov 20 '18 at 7:53
which compiler are you using? Nothing wrong with your code. Please post the exact error message and a Minimal, Complete, and Verifiable example
– Alan Birtles
Nov 20 '18 at 7:53
I am very sorry, I use this software for the first time, many things do not understand, thank you for explaining to me
– dou
Nov 20 '18 at 7:54
I am very sorry, I use this software for the first time, many things do not understand, thank you for explaining to me
– dou
Nov 20 '18 at 7:54
An error is reported on the The third last line line: the expression must contain pointer type
– dou
Nov 20 '18 at 7:56
An error is reported on the The third last line line: the expression must contain pointer type
– dou
Nov 20 '18 at 7:56
3
3
@dou Unrelated: In C++ you have a better option. Its called
std::vector<>. And as usual, the question would be; is there any special reason that you are not using it?– JeJo
Nov 20 '18 at 8:01
@dou Unrelated: In C++ you have a better option. Its called
std::vector<>. And as usual, the question would be; is there any special reason that you are not using it?– JeJo
Nov 20 '18 at 8:01
@JeJo:Can you give me an example of code usage?I do not have the programming foundation, a lot of basic knowledge do not understand, can only learn from the program example
– dou
Nov 20 '18 at 8:11
@JeJo:Can you give me an example of code usage?I do not have the programming foundation, a lot of basic knowledge do not understand, can only learn from the program example
– dou
Nov 20 '18 at 8:11
|
show 4 more comments
1 Answer
1
active
oldest
votes
0
This may be all you need -
Approach 1: Using a simple 2-D array
#include <iostream>
using namespace std;
int main()
{
int dimension1, dimension2 = 5;
cout << "Enter first dimension : " << endl;
cin >> dimension1;
// dynamic allocation
int** array2d = new int*[dimension1];
for(int i = 0; i < dimension1; ++i)
array2d[i] = new int[dimension2];
/*
// you may fill it with your values
for(int i = 0; i < dimension1; ++i)
for(int j = 0; j < dimension2; ++j)
array2d[i][j] = i;
*/
// print
for(int i = 0; i < dimension1; ++i) {
for(int j = 0; j < dimension2; ++j) {
cout << array2d[i][j] << " ";
}
cout << endl;
}
// free
for(int i = 0; i < dimension1; ++i)
delete array2d[i];
delete array2d;
return 0;
}
Sample Output :
Enter first dimension :
4
0 0 0 0 0
0 0 0 0 0
0 0 0 0 0
0 0 0 0 0
Approach 2: Using Vectors -
#include <iostream>
#include <vector>
using namespace std;
int main()
{
// size of row
int rowSize;
int colSize = 5;
cout << "Enter row size : ";
cin >> rowSize;
// Create a vector of vector with size equal to rowSize; filled with 0.
vector<vector<int>> vec(rowSize, vector<int>(colSize));
for (int i = 0; i < rowSize; i++) {
for (int j = 0; j < vec[i].size(); j++)
cout << vec[i][j] << " ";
cout << endl;
}
vec.clear();
return 0;
}
Sample Output :
Enter row size : 3
0 0 0 0 0
0 0 0 0 0
0 0 0 0 0
answered Nov 20 '18 at 7:21
Tushar WalzadeTushar Walzade
1,82331630
2
Usestd::vector.
– Fantastic Mr Fox
Nov 20 '18 at 7:36
if (b_bump_num == 0) { int bump[1]={0}; } else { int** bump=new int*[n]; for(int i=0;i<b_bump_num;++i) { bump[i]=new int[5]; } } for(int i=0;i<b_bump_num;++i) delete bump[i]; delete bump;(An error is reported on the penultimate line: the expression must contain pointer type)
– dou
Nov 20 '18 at 7:45
@Tushar Walzade:Thank you very much.
– dou
Nov 20 '18 at 8:43
add a comment |
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1 Answer
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1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
0
This may be all you need -
Approach 1: Using a simple 2-D array
#include <iostream>
using namespace std;
int main()
{
int dimension1, dimension2 = 5;
cout << "Enter first dimension : " << endl;
cin >> dimension1;
// dynamic allocation
int** array2d = new int*[dimension1];
for(int i = 0; i < dimension1; ++i)
array2d[i] = new int[dimension2];
/*
// you may fill it with your values
for(int i = 0; i < dimension1; ++i)
for(int j = 0; j < dimension2; ++j)
array2d[i][j] = i;
*/
// print
for(int i = 0; i < dimension1; ++i) {
for(int j = 0; j < dimension2; ++j) {
cout << array2d[i][j] << " ";
}
cout << endl;
}
// free
for(int i = 0; i < dimension1; ++i)
delete array2d[i];
delete array2d;
return 0;
}
Sample Output :
Enter first dimension :
4
0 0 0 0 0
0 0 0 0 0
0 0 0 0 0
0 0 0 0 0
Approach 2: Using Vectors -
#include <iostream>
#include <vector>
using namespace std;
int main()
{
// size of row
int rowSize;
int colSize = 5;
cout << "Enter row size : ";
cin >> rowSize;
// Create a vector of vector with size equal to rowSize; filled with 0.
vector<vector<int>> vec(rowSize, vector<int>(colSize));
for (int i = 0; i < rowSize; i++) {
for (int j = 0; j < vec[i].size(); j++)
cout << vec[i][j] << " ";
cout << endl;
}
vec.clear();
return 0;
}
Sample Output :
Enter row size : 3
0 0 0 0 0
0 0 0 0 0
0 0 0 0 0
answered Nov 20 '18 at 7:21
Tushar WalzadeTushar Walzade
1,82331630
2
Usestd::vector.
– Fantastic Mr Fox
Nov 20 '18 at 7:36
if (b_bump_num == 0) { int bump[1]={0}; } else { int** bump=new int*[n]; for(int i=0;i<b_bump_num;++i) { bump[i]=new int[5]; } } for(int i=0;i<b_bump_num;++i) delete bump[i]; delete bump;(An error is reported on the penultimate line: the expression must contain pointer type)
– dou
Nov 20 '18 at 7:45
@Tushar Walzade:Thank you very much.
– dou
Nov 20 '18 at 8:43
add a comment |
0
This may be all you need -
Approach 1: Using a simple 2-D array
#include <iostream>
using namespace std;
int main()
{
int dimension1, dimension2 = 5;
cout << "Enter first dimension : " << endl;
cin >> dimension1;
// dynamic allocation
int** array2d = new int*[dimension1];
for(int i = 0; i < dimension1; ++i)
array2d[i] = new int[dimension2];
/*
// you may fill it with your values
for(int i = 0; i < dimension1; ++i)
for(int j = 0; j < dimension2; ++j)
array2d[i][j] = i;
*/
// print
for(int i = 0; i < dimension1; ++i) {
for(int j = 0; j < dimension2; ++j) {
cout << array2d[i][j] << " ";
}
cout << endl;
}
// free
for(int i = 0; i < dimension1; ++i)
delete array2d[i];
delete array2d;
return 0;
}
Sample Output :
Enter first dimension :
4
0 0 0 0 0
0 0 0 0 0
0 0 0 0 0
0 0 0 0 0
Approach 2: Using Vectors -
#include <iostream>
#include <vector>
using namespace std;
int main()
{
// size of row
int rowSize;
int colSize = 5;
cout << "Enter row size : ";
cin >> rowSize;
// Create a vector of vector with size equal to rowSize; filled with 0.
vector<vector<int>> vec(rowSize, vector<int>(colSize));
for (int i = 0; i < rowSize; i++) {
for (int j = 0; j < vec[i].size(); j++)
cout << vec[i][j] << " ";
cout << endl;
}
vec.clear();
return 0;
}
Sample Output :
Enter row size : 3
0 0 0 0 0
0 0 0 0 0
0 0 0 0 0
answered Nov 20 '18 at 7:21
Tushar WalzadeTushar Walzade
1,82331630
2
Usestd::vector.
– Fantastic Mr Fox
Nov 20 '18 at 7:36
if (b_bump_num == 0) { int bump[1]={0}; } else { int** bump=new int*[n]; for(int i=0;i<b_bump_num;++i) { bump[i]=new int[5]; } } for(int i=0;i<b_bump_num;++i) delete bump[i]; delete bump;(An error is reported on the penultimate line: the expression must contain pointer type)
– dou
Nov 20 '18 at 7:45
@Tushar Walzade:Thank you very much.
– dou
Nov 20 '18 at 8:43
add a comment |
0
0
0
This may be all you need -
Approach 1: Using a simple 2-D array
#include <iostream>
using namespace std;
int main()
{
int dimension1, dimension2 = 5;
cout << "Enter first dimension : " << endl;
cin >> dimension1;
// dynamic allocation
int** array2d = new int*[dimension1];
for(int i = 0; i < dimension1; ++i)
array2d[i] = new int[dimension2];
/*
// you may fill it with your values
for(int i = 0; i < dimension1; ++i)
for(int j = 0; j < dimension2; ++j)
array2d[i][j] = i;
*/
// print
for(int i = 0; i < dimension1; ++i) {
for(int j = 0; j < dimension2; ++j) {
cout << array2d[i][j] << " ";
}
cout << endl;
}
// free
for(int i = 0; i < dimension1; ++i)
delete array2d[i];
delete array2d;
return 0;
}
Sample Output :
Enter first dimension :
4
0 0 0 0 0
0 0 0 0 0
0 0 0 0 0
0 0 0 0 0
Approach 2: Using Vectors -
#include <iostream>
#include <vector>
using namespace std;
int main()
{
// size of row
int rowSize;
int colSize = 5;
cout << "Enter row size : ";
cin >> rowSize;
// Create a vector of vector with size equal to rowSize; filled with 0.
vector<vector<int>> vec(rowSize, vector<int>(colSize));
for (int i = 0; i < rowSize; i++) {
for (int j = 0; j < vec[i].size(); j++)
cout << vec[i][j] << " ";
cout << endl;
}
vec.clear();
return 0;
}
Sample Output :
Enter row size : 3
0 0 0 0 0
0 0 0 0 0
0 0 0 0 0
answered Nov 20 '18 at 7:21
Tushar WalzadeTushar Walzade
1,82331630
This may be all you need -
Approach 1: Using a simple 2-D array
#include <iostream>
using namespace std;
int main()
{
int dimension1, dimension2 = 5;
cout << "Enter first dimension : " << endl;
cin >> dimension1;
// dynamic allocation
int** array2d = new int*[dimension1];
for(int i = 0; i < dimension1; ++i)
array2d[i] = new int[dimension2];
/*
// you may fill it with your values
for(int i = 0; i < dimension1; ++i)
for(int j = 0; j < dimension2; ++j)
array2d[i][j] = i;
*/
// print
for(int i = 0; i < dimension1; ++i) {
for(int j = 0; j < dimension2; ++j) {
cout << array2d[i][j] << " ";
}
cout << endl;
}
// free
for(int i = 0; i < dimension1; ++i)
delete array2d[i];
delete array2d;
return 0;
}
Sample Output :
Enter first dimension :
4
0 0 0 0 0
0 0 0 0 0
0 0 0 0 0
0 0 0 0 0
Approach 2: Using Vectors -
#include <iostream>
#include <vector>
using namespace std;
int main()
{
// size of row
int rowSize;
int colSize = 5;
cout << "Enter row size : ";
cin >> rowSize;
// Create a vector of vector with size equal to rowSize; filled with 0.
vector<vector<int>> vec(rowSize, vector<int>(colSize));
for (int i = 0; i < rowSize; i++) {
for (int j = 0; j < vec[i].size(); j++)
cout << vec[i][j] << " ";
cout << endl;
}
vec.clear();
return 0;
}
Sample Output :
Enter row size : 3
0 0 0 0 0
0 0 0 0 0
0 0 0 0 0
answered Nov 20 '18 at 7:21
Tushar WalzadeTushar Walzade
1,82331630
edited Nov 20 '18 at 8:50
answered Nov 20 '18 at 7:21
Tushar WalzadeTushar Walzade
1,82331630
answered Nov 20 '18 at 7:21
Tushar WalzadeTushar Walzade
1,82331630
answered Nov 20 '18 at 7:21
Tushar WalzadeTushar Walzade
1,82331630
1,82331630
2
Usestd::vector.
– Fantastic Mr Fox
Nov 20 '18 at 7:36
if (b_bump_num == 0) { int bump[1]={0}; } else { int** bump=new int*[n]; for(int i=0;i<b_bump_num;++i) { bump[i]=new int[5]; } } for(int i=0;i<b_bump_num;++i) delete bump[i]; delete bump;(An error is reported on the penultimate line: the expression must contain pointer type)
– dou
Nov 20 '18 at 7:45
@Tushar Walzade:Thank you very much.
– dou
Nov 20 '18 at 8:43
add a comment |
2
Usestd::vector.
– Fantastic Mr Fox
Nov 20 '18 at 7:36
if (b_bump_num == 0) { int bump[1]={0}; } else { int** bump=new int*[n]; for(int i=0;i<b_bump_num;++i) { bump[i]=new int[5]; } } for(int i=0;i<b_bump_num;++i) delete bump[i]; delete bump;(An error is reported on the penultimate line: the expression must contain pointer type)
– dou
Nov 20 '18 at 7:45
@Tushar Walzade:Thank you very much.
– dou
Nov 20 '18 at 8:43
2
2
Use
std::vector.– Fantastic Mr Fox
Nov 20 '18 at 7:36
Use
std::vector.– Fantastic Mr Fox
Nov 20 '18 at 7:36
if (b_bump_num == 0) { int bump[1]={0}; } else { int** bump=new int*[n]; for(int i=0;i<b_bump_num;++i) { bump[i]=new int[5]; } } for(int i=0;i<b_bump_num;++i) delete bump[i]; delete bump;(An error is reported on the penultimate line: the expression must contain pointer type)
– dou
Nov 20 '18 at 7:45
if (b_bump_num == 0) { int bump[1]={0}; } else { int** bump=new int*[n]; for(int i=0;i<b_bump_num;++i) { bump[i]=new int[5]; } } for(int i=0;i<b_bump_num;++i) delete bump[i]; delete bump;(An error is reported on the penultimate line: the expression must contain pointer type)
– dou
Nov 20 '18 at 7:45
@Tushar Walzade:Thank you very much.
– dou
Nov 20 '18 at 8:43
@Tushar Walzade:Thank you very much.
– dou
Nov 20 '18 at 8:43
add a comment |
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which compiler are you using? Nothing wrong with your code. Please post the exact error message and a Minimal, Complete, and Verifiable example
– Alan Birtles
Nov 20 '18 at 7:53
I am very sorry, I use this software for the first time, many things do not understand, thank you for explaining to me
– dou
Nov 20 '18 at 7:54
An error is reported on the The third last line line: the expression must contain pointer type
– dou
Nov 20 '18 at 7:56
3
@dou Unrelated: In C++ you have a better option. Its called
std::vector<>. And as usual, the question would be; is there any special reason that you are not using it?– JeJo
Nov 20 '18 at 8:01
@JeJo:Can you give me an example of code usage?I do not have the programming foundation, a lot of basic knowledge do not understand, can only learn from the program example
– dou
Nov 20 '18 at 8:11