Is Integer Factorization Harder Than RSA Factorization?

What is wrong with my c program? prime factorization?

• my program works well but the only problem is in never outputs hte number 2. when i enter the integer 18 its supposed to spit out the prime factorization which is 2 3 3 but it gives me 3 3. whats wrong... #include<stdio.h> int main() { while(3){ printf("\nEnter an integer: "); int n, x, y, z, k; k = 2; x = 2; while(2){ scanf("%d", &n); if (n <= 1) return (0); if (n > 1) break; } printf("The prime factorization of %d is ",n); while(1){ if (n % k == 0) (n = (n/k)); if (n % k != 0) (k = k + 1); if(k > n) break; if (n % k == 0) printf("%d ",k); } } printf("\n"); return 0; }

• Answer:

  Try this though it is crude #include<stdio.h> #include<stdlib.h> int main() { int i,n,rn,r=1,j,k; printf("enter an integer\n"); scanf("%d", &n); rn=n; for(j=2;(r!=rn&&n>1)&&j<n;j++) { for(k=2;k<j;k++) { if(j%k==0)break; } if(j==k){ while(n%j==0){ printf("%d ", j); r=r*j; n=n/j; } } } system("PAUSE"); return 0; }