What is the problem with the following code? C compiler shows me error: Segmentation fault.
#include <stdio.h>
#include <math.h>
int main() {
int n = 4;
float A[n][n][n][n];
A[n][n][1][1] = 1;
A[n][n][1][2] = 0;
A[n][n][1][3] = -3;
A[n][n][1][4] = 0;
A[n][n][2][1] = 1;
A[n][n][2][2] = 0;
A[n][n][2][3] = -3;
A[n][n][2][4] = 0;
return 0;
}
If you define an array of length N, the access to the last element is at the N-1 index, and the access to the first element is at index 0 because indexes start from 0 and end at N-1.
So your code should be like this:
#include<stdio.h>
#include<math.h>
#define N 4
int main() {
float A[N][N][N][N];
A[N-1][N-1][0][0]=1;
A[N-1][N-1][0][1]=0;
A[N-1][N-1][0][2]=-3;
A[N-1][N-1][0][3]=0;
A[N-1][N-1][1][0]=1;
A[N-1][N-1][1][1]=0;
A[N-1][N-1][1][2]=-3;
A[N-1][N-1][1][3]=0;
return 0;
}
Also, you're using a variable to define the length of your array, which is good only in the C99 standard and onwards. If you don't need a VLA (variable length array), you should use the #define instead.