Hackerrank Weekly challenges Week 8 - John and GCD list solution

Hackerrank Weekly challenges Week 8 - John and GCD list: https://www.hackerrank.com/contests/w8/challenges/john-and-gcd-list

Hackerrank Weekly challenges Week 8 - John and GCD list solution: http://ideone.com/QZZxNC

#include <iostream>
#include <cstdio>

int gcd(int u, int v) {
    if(u==v) return u;
    if(u==0) return v;
    if(v==0) return u;
    if(~u&1) {
        if(v&1) return gcd(u>>1, v);
        return gcd(u>>1, v>>1)<<1;
    }
    if(~v&1) return gcd(u, v>>1);
    if(u>v) return gcd((u-v)>>1, v);
    return gcd((v-u)>>1, u);
}

int lcm(int u, int v) {
    return u*v/gcd(u, v);
}

int main() {
    int t, n, a[1005], b[1005];
    scanf("%d", &t);
    while(t--) {
        scanf("%d", &n);
        for(int i=0; i<n; i++) scanf("%d", &a[i]);
        b[0]=a[0];
        for(int i=1; i<n; i++) b[i]=lcm(a[i-1], a[i]);
        b[n]=a[n-1];
        for(int i=0; i<=n; i++) printf("%d ", b[i]);
        printf("\n");
    }
    return 0;
}