HDU-4647 Another Graph Game 貪心

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將邊權拆成兩半加到它所關聯的兩個點的點權中即可。因為當兩個人分別選擇不同的點時，這一權值將互相抵消。然後排序從最優開始取。

#include <iostream>#include <cstdio>#include <cmath>#include <queue>#include <algorithm>#include <iomanip>#include <cstring>#include <vector>#define LL long longusing namespace std;const int maxn=110000;bool cmp(LL a, LL b){return a>b;}LL n,m;LL w[maxn];int main(){LL u,v,l;while(scanf("%I64d%I64d",&n,&m)!=EOF){for(LL i=1;i<=n;i++){scanf("%I64d",&w[i]);w[i]*=2ll;}for(LL i=0;i<m;i++){scanf("%I64d%I64d%I64d",&u,&v,&l);w[u]+=l;w[v]+=l;}sort(w+1,w+1+n,cmp);LL k=1;LL s1=0ll;LL s2=0ll;while(k<=n){if(k%2==1){s1+=w[k];}else{s2+=w[k];}k++;}LL ans=s1-s2;printf("%I64d\n",ans/2);}return 0;}

HDU-4647 Another Graph Game 貪心