#include; int main(void) { int i=1,n=5000,s=0,j=0; printf("it is runing\n"); for(i=1; i { s=0; for(j=1; j { if(i%j==0) { s=j+s; //printf("s=%d\n",s); } } if(s==i) { printf("%d is perfect number.\n",j); } } return 0; }