Eugene and an array Codeforces Round #632 (Div. 2)
传送门#include#definelllonglongusingnamespacestd;constintmaxn=2e5+10;intn,x;mapm;intmain(){scanf("%d",&n);llpref=0,ans=0;intl=0;m[0]=0;for(inti=1;i<=n;++i){scanf("%d",&x);pref+=x;if(m.count(pref))l=max(l