for each given N find it's prime factors problem propsed in scorify challange .

primes.cpp

#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>


int nextInt(){
  int a; scanf("%d", &a); return a;
}
int nextLong(){
  long long a; scanf("%lld", &a); return a;
}

int m, n;
const int N = 1e5 + 10;

int main() {
 
  
  int seive[N];
  int list[1000];
  
  /* the pre processing part */
  
  seive[1] = 1;
  for (int i = 2; i < N; i++)
    seive[i] = i;
  for (int i = 4; i < N; i += 2)
    seive[i] = 2;

  for (int i = 3; i * i < N; i++) {
    if (seive[i] == i) {
      for (int j = i * i; j < N; j += i)
        if (seive[j] == j)
        seive[j] = i;
    }
  }
  
  int t = nextInt();
  
  /* answer queries in O(log(N)) per query */
  
  for (int tc = 1; tc <= t; tc++){
    n = nextInt();
    int j = 0;
    while (n != 1) {
      list[j++] = (seive[n]);
      n = n / seive[n];
    }
    for(int i = 0; i < j; i++){
      if(i > 0) printf(" ");
      printf("%d", list[i]);
    }
    printf("\n");
    
  }

  return 0;
}

https://gist.github.com/Eroui/683460267867a290e91e9c71f8b1fdfc
A few modifications x)