Printing 2D arrays? [closed] - c++

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I have encountered a problem with printing 2D arrays. Here is my code, any help will be greatly appreciated.
#include<iostream>
using namespace std;
int main()
{
int NumRow, NumColumn;
int anArray[2][2] = {{1,2},{3,4}};
for (int N_column = 1; N_column < NumColumn; N_column++)
{
for (int N_row = 1; N_row < NumRow; N_row++)
{
cout << anArray[N_row,N_column];
}
}
return 0;
}

Answer 1

3 problems:
Array indexes start at 0.
NumColumn, NumRow are uninitialized.
wrong syntax [y,j], use [i][j]
Try like this:
...
int NumRow = 2, NumColumn = 2;
int anArray[2][2] = {{1,2},{3,4}};
for (int N_column = 0; N_column < NumColumn; N_column++)
{
for (int N_row = 0; N_row < NumRow; N_row++)
{
cout << anArray[N_row][N_column];
}
}
...

Answer 2

You declare
int NumRow, NumColumn;
but you never assign a value to them. Use
int NumRow = 2, NumColumn = 2;
instead. Also, C-arrays start at 0, not at 1, so you must update your for-loops as well:
for (int N_column = 0; ...
for (int N_row = 0; ...
Last, change the output statement, as multidimensional arrays need to be reached in a different way:
cout << anArray[N_row][N_column];

Answer 3

There are few issues in your code:
1st: You declare NumRow, NumColumn but use them without initializing them before which cause to Undefined Behaviour.
Solution: Initialized them
NumRow = 2;
NumColumn = 2;
2nd: Array syntax in the following line-
cout << anArray[N_row,N_column];
it should be
cout << anArray[N_row][N_column];
3rd: C++ arrays are zero indexed, so you should start initializing the loop control variables like following:
for (int N_column = 0; N_column < NumColumn; N_column++)
{ ^^^
for (int N_row = 0; N_row < NumRow; N_row++)
{ ^^^^
//...