PAT 1007. Maximum Subsequence Sum

#include<cstdio>#include<algorithm>#include<iostream>#include<vector>#include<string.h>using namespace std;int n;int num[10010];int main(){//freopen("G://test.txt","r",stdin);while(scanf("%d",&n)!=EOF){for(int i=0;i<n;++i){scanf("%d",&num[i]);}int maxn=0;int st=-1;int end=-1;int flag=0;int temp;int fal=0,fale=-1,fals=-1;for(int i=0;i<n;++i){if(num[i]>=0){if(maxn<0){flag=0;maxn=0;}if(flag==0){flag=1;st=i;}maxn+=num[i];end=i;if(maxn>fal){fals=st;fal=maxn;fale=end;}}else{maxn+=num[i];}}if(st==-1)printf("%d %d %d\n",0,num[0],num[n-1]);else{printf("%d %d %d\n",fal,num[fals],num[fale]);}}return 0;}