蓝桥15/B/5/拔河

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#pragma GCC optimize("O3,unroll-loops")
#include<bits/stdc++.h>
using namespace std;const int N=1e3+10;
int n;
long long a[N];int main()
{ios::sync_with_stdio(0),cin.tie(0);cin>>n;for(int i=1;i<=n;i++) cin>>a[i];int l1=1,l2=2;set<long long> st;long long ans=2e18;for(l2=2;l2<=n;l2++,l1++){long long sum1=0;for(int r1=l1;r1<=n;r1++){sum1+=a[r1];st.insert(sum1);}long long sum2=0;for(int r2=l2;r2<=n;r2++){sum2+=a[r2];if(!st.empty()){auto ps = st.lower_bound(sum2);if(ps!=st.end()){ans=min(ans,*ps-sum2);}if(ps!=st.begin()){ans=min(ans,sum2-*prev(ps));}}}}cout<<ans<<"\n";return 0;}