47 lines
869 B
C++
47 lines
869 B
C++
#include<cstdio>
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#include<cstring>
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#include<algorithm>
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using namespace std;
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const int maxn=20005;
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const int maxm=100005;
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struct ZF { int a,b,c; };
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inline bool operator<(const ZF &x,const ZF &y) { return x.c>y.c; }
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int n,m,fa[maxn*2];
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ZF zf[maxm];
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inline int ff(int u)
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{
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int a=u,b;
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while(u!=fa[u]) u=fa[u];
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while(a!=u)
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{
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b=fa[a];
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fa[a]=u;
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a=b;
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}
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return u;
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}
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inline void merge(int a,int b)
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{
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a=ff(a); b=ff(b);
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fa[a]=b;
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}
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int main()
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{
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#ifdef local
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freopen("pro.in","r",stdin);
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#endif
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scanf("%d%d",&n,&m);
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for(int i=1;i<=m;i++) scanf("%d%d%d",&zf[i].a,&zf[i].b,&zf[i].c);
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sort(zf+1,zf+m+1);
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for(int i=1;i<=n*2;i++) fa[i]=i;
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for(int i=1;i<=m;i++)
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{
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int ax=zf[i].a*2,ay=zf[i].a*2-1;
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int bx=zf[i].b*2,by=zf[i].b*2-1;
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merge(ax,by);
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merge(ay,bx);
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if(ff(ax)==ff(ay)||ff(bx)==ff(by)) { printf("%d\n",zf[i].c); return 0; }
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}
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puts("0");
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return 0;
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} |