uva11093贪心算法

//uva11093
//贪心算法，加油站环路，O(n)
#include<iostream>
#include<algorithm>
#include<cstdio>
using namespace std;
const int N = 100005;
int n,res,i,j,d,T,t,s;
int p[N], x[N];

int main()
{
	scanf("%d", &T);
	for (j = 1; j <= T;j++) {
		scanf("%d", &n);
		for (i = 0; i < n; i++) {
			scanf("%d", &p[i]);
		}
		for (i = 0; i < n; i++) {
			scanf("%d", &x[i]);
		}
		d =t=s=i= 0;
		while(t<n) {
			d = d+p[i] - x[i];
			i = (i + n + 1) % n;
			if (d < 0) {
				if (s >= i) break; 
				d = 0; s = i; t = 0;
			}
			else t++;
		}
		if(t<n) printf("Case %d: Not possible\n", j); 
		else printf("Case %d: Possible from station %d\n",j,s+1);
	}
	return 0;
}
//system("pause");

/*
20
5
1 1 1 1 1
1 1 2 1 1
7
1 1 1 10 1 1 1
2 2 2 2 2 2 2

*/