Uva 11093 Just Finish it up

 1 #include<iostream>  
 2 #include<cstdio>  
 3 #include<cstring> 
 4 #include <cmath> 
 5 #include<stack>
 6 #include<vector>
 7 #include<map> 
 8 #include<set>
 9 #include<queue> 
10 #include<algorithm>  
11 using namespace std;
12 
13 #define foreach(i,c) for (__typeof(c.begin()) i = c.begin(); i != c.end(); ++i)
14 
15 typedef long long LL;
16 const int INF = (1<<30)-1;
17 const int mod=1000000007;
18 const int maxn=1000005;
19 
20 int p[maxn],q[maxn];
21 
22 int main(){
23     int T;
24     scanf("%d",&T);
25     int kase=0;
26     while(T--){
27         int n;
28         cin>>n;
29         for(int i=0;i<n;i++) cin>>p[i];
30         for(int i=0;i<n;i++) cin>>q[i];
31         
32         int pos;
33         int i=0,flag;
34         while(i<n){
35             int ans=0;
36             flag=1;
37             
38             for(int j=0;j<n;j++){
39                 pos=(j+i)%n;
40         
41                 ans+=p[pos];
42                 ans-=q[pos];
43                 if(ans<0){
44                     flag=0;
45                     break;
46                 }
47             }
48             
49             if(flag) break;
50             if(pos<i) {//重复了，说明已经枚举完一圈可能的，都还是没有找到可能的起点，跳出 
51                 flag=0;break;
52             }
53             i=pos+1;
54         }
55     
56         printf("Case %d: ",++kase);
57         if(flag) printf("Possible from station %d\n",i+1);
58         else printf("Not possible\n");    
59     }
60     return 0;
61 }