arrays - Write a function to compute the n'th power of a (nxn)matrix in C -

i've added multiplication of 2 matrices algorithm seems it's not working.i need task without using pointers,memory allocation , using basic instructions(for's,while's,...)

void product(double a[][20],double c[][20],int n,int d) {     int i, j, k, l;      for(l = 1;l <= d; ++l) {         for(i = 0; < n; i++) {             for(j = 0; j < n; j++) {                 c[i][j] = 0;                 for(k = 0; k < n; k++) {                     c[i][j] += a[i][k]*a[k][j];                 }              }          }      } } 

this function should calculate a^d , store in c[][20];

your code tries compute a^(2^d), instead calculates a^2 d times.

you can't matrix multiplication in place, because calculate result, overwrite values. need temporary space 1 copy (unless d = 0, 1 or 2).

set c identity matrix , return if d = 0. otherwise set c = copy of a, allocate matrix b, l = 1 d - 1 copy c b, let c = * b.. deallocate b.