how can i solve this?

Question

i want to multiply to matrix and matrix elements are ok but output is wrong
why?
#include <stdio.h>
#include <math.h>
int main()
{
int reza[10][10];
int reza2[10][10];
int reza3[10][10];
int x,y,z,n;
int i,j,k,l;
int a,r,sum;
sum=0;
scanf("%d",&x);
scanf("%d",&y);
scanf("%d",&z);
scanf("%d",&n);
if(y!=z)
{
printf("NO\n");
}
else
{
for(i=0;i<x;i++)
{
for(j=0;j<y;j++)
{
a=pow(i+1,j);
printf("reza[%d][%d]=%d\n",i,j,reza[i][j]=a);
}
}
for(k=0;k<z;k++)
{
for(l=0;l<n;l++)
{
printf("reza1[%d][%d]=%d\n",k,l,reza2[i][j]=(k+1)*l);
}
}
for (i=0;i<x;i++)
{
for (j=0;j<n;j++)
{
for (r=0;r<y;r++)
{
sum=sum+(reza[i][r]*reza2[r][j]);
}
reza3[i][j]=sum;
sum=0;
}
}
for (i=0;i<x;i++)
{
for (j=0;j<n;j++)
{
printf("%d\n", reza3[i][j]);
}
}
}
return 0;
}

Answer 1

thank you Martin