题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=1422
1 #include<iostream> 2 #include<cstdio> 3 #include<cstring> 4 #include<algorithm> 5 using namespace std; 6 #define MAXN 222222 7 int level[MAXN]; 8 int dp[MAXN]; 9 int n,w,l; 10 11 int main(){ 12 while(~scanf("%d",&n)){ 13 int st=0,ans=0,now=0; 14 memset(dp,0,sizeof(dp)); 15 for(int i=1;i<=n;i++){ 16 scanf("%d%d",&w,&l); 17 level[i]=level[i+n]=w-l; 18 } 19 for(int i=1;i<=2*n;i++){ 20 if(now+level[i]>=0){ 21 now+=level[i]; 22 dp[i]=dp[i-1]+1; 23 //最多n个城市 24 if(i-st==n){ 25 ans=max(ans,dp[i]); 26 break; 27 } 28 }else { 29 now=0,st=i;//注意这里st应该改为i. 30 dp[i]=0; 31 ans=max(ans,dp[i-1]); 32 } 33 } 34 printf("%d\n",ans); 35 } 36 return 0; 37 }