CODE TUNING

#include<stdio.h>
#include<math.h>
main()
{
int i,j,k,r,a[10][10],b[10][10],sum=0,m;
printf("enter a 3/3 matrix\n");
for(i=1;i<=3;i++)
for(j=1;j<=3;j++)
{

printf("enter (%d of %d)\t ",i,j);
scanf("%d",&a[i][j]);
}
printf("your matrix is \n");
for(i=1;i<=3;i++)
{
for(j=1;j<=3;j++)
{
printf("\t%d",a[i][j]);
b[i][j]=0;
}
printf("\n");
}
for(i=1;i<=3;i++)
{
for(j=2,m=1;j<=3;j++,m++)
for(r=1,k=1;k<=3;k++)
if(k!=i)
{
b[m][r]=a[j][k];
r++;
}
sum=sum+pow(-1,i+1)*a[1][i]*(b[1][1]*b[2][2]-b[1][2]*b[2][1]);
}
printf("determinant of matrix is =%d  ",sum);
}