GCD and LCM Problem Code: FLOW016

A solution in c++

#include<stdio.h>


int gcd(long long int n, long long int m);
int lcm(int n, int m);

int main()
{
    long long int a,b,i,j,m,n,ck=0,dk=0;
    scanf("%lld", &a);
    while(a--){
    scanf("%lld %lld", &n, &m);
    ck = gcd(n,m);
    dk = (n*m)/gcd(n,m);
    printf("%lld %lld\n",ck, dk);
    }
}

int gcd(long long int n, long long int m)
{
    //if(n<m) swap(n,m);
    if(m==0) return n;
    else return gcd(m, n%m);
}