#include <cstdio>

#include <cstring>

#include <cmath>

#include <iostream>

#include <algorithm>

#include <queue>

#include <cstdlib>

#include <vector>

#include <set>

#include <map>

#define LL long long

#define mod 1000000007

#define inf 1<<30

#define N 2010

using namespace std;

int a[N],dp[N];

int c[N];

int main()

{

    int t,n;

    scanf("%d",&t);

    while(t--)

    {

        scanf("%d",&n);

        for(int i=;i<=n;i++)scanf("%d",&a[i]);

        for(int i=;i<=n;i++)scanf("%d",&c[i]);

        memset(dp,,sizeof(dp));

        dp[]=a[];

        for(int i=;i<=n;i++)dp[i]=min(dp[i-]+c[i],dp[i-]+a[i]);

        int sum=dp[n];

        int h=sum/+;

        int m=(sum%)/;

        int s=sum%;

        printf("%02d:%02d:%02d",h,m,s);

        if(h>=)printf(" pm\n");

        else printf(" am\n");

    }

}