Input values from scanf but prints different values - c

Question

I input the values from scanf but when i print them, all the columns have the last row's values.
#include <stdio.h>
int main(){
int N, M;
int A[N][M];
int T[N][M];
int i,j;
printf("Insert number of rows and columns: ");
scanf("%d %d",&N,&M);
printf("\nInsert the matrix\n");
for(i=0; i<N; i++){
for(j=0; j<M; j++){
scanf("%d", &A[i][j]);
}
}
printf("\nInserted matrix:\n");
for(i=0; i<N; i++){
for(j=0; j<M; j++){
printf("%d ",A[i][j]);
}
printf("\n");
}
return 0;
}
I've tried checking if it's a index problem and printing each element with its coordinate but that seems to be fine, the problem must be somewhere in the scanf.
Input:
Insert number of rows and columns: 3 3
Insert the matrix
1 2 3
4 5 6
7 8 9
output:
Inserted matrix:
7 8 9
7 8 9
7 8 9

Answer 1

Turn on compiler warnings. Any decent compiler will warn you that in:
int N, M;
int A[N][M];
N and M are not initialized. Because they are not initialized, you do not know what int A[N][M]; will do. The array dimensions must be known when the declaration is reached.
You can move int A[N][M]; and int T[N][M]; to after the scanf that reads N and M.
Note that declaring arrays with variable lengths is not suitable for general code. It can be used for simple school assignments, but you should eventually progress to using malloc and other techniques. (Variable length arrays can also be used where the size is known to be within certain limits.)

Answer 2

the following proposed code:
cleanly compiles
performs the desired functionality
fails to check for errors when calling scanf()
and now, the proposed code:
#include <stdio.h>
int main( void )
{
int N, M;
printf("Insert number of rows and columns: ");
scanf("%d %d",&N,&M);
int A[N][M];
//int T[N][M];
int i,j;
printf("\nInsert the matrix\n");
for(i=0; i<N; i++)
{
for(j=0; j<M; j++)
{
scanf("%d", &A[i][j]);
}
}
printf("\nInserted matrix:\n");
for(i=0; i<N; i++)
{
for(j=0; j<M; j++)
{
printf("%d ",A[i][j]);
}
printf("\n");
}
return 0;
}
When run with the input:
3 3
1 2 3 4 5 6 7 8 9
The output is:
Insert number of rows and columns: 3 3
Insert the matrix
1 2 3 4 5 6 7 8 9
Inserted matrix:
1 2 3
4 5 6
7 8 9
The critical difference between the OPs posted code and this answer is the initialization of 'N' and 'M' before they are used in defining the size of the array: A[N][M]