关押罪犯
带权并查集+贪心+排序
1 #include <cstdio> 2 #include <algorithm> 3 using namespace std; 4 struct data {int x,y,z;}; 5 data f[100005]; 6 int n,m,a[20005],b[20005],i; 7 inline bool cmp(data a,data b) 8 { 9 return a.z>b.z; 10 } 11 inline int find(int x) 12 { 13 if(a[x]==x) return x; 14 a[x]=find(a[x]); 15 return a[x]; 16 } 17 inline void ad(int x,int y) 18 { 19 x=find(a[x]); 20 y=find(a[y]); 21 a[x]=y; 22 } 23 inline bool check(int x,int y) 24 { 25 x=find(x); 26 y=find(y); 27 if(x==y) return true; 28 return false; 29 } 30 int main() 31 { 32 scanf("%d%d",&n,&m); 33 for(i=1;i<=n;i++) a[i]=i; 34 for(i=1;i<=m;i++) 35 scanf("%d%d%d",&f[i].x,&f[i].y,&f[i].z); 36 sort(f+1,f+m+1,cmp); 37 for(i=1;i<=m+1;i++) 38 { 39 if(check(f[i].x,f[i].y)) {printf("%d",f[i].z);break;} 40 else 41 { 42 if(!b[f[i].x]) b[f[i].x]=f[i].y; 43 else {ad(b[f[i].x],f[i].y);} 44 if(!b[f[i].y]) b[f[i].y]=f[i].x; 45 else {ad(b[f[i].y],f[i].x);} 46 } 47 } 48 return 0; 49 }
