挺简单的floyd
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// <1491.cpp> - 01/04/17 21:36:25 // This file is created by XuYike's black technology automatically. // Copyright (C) 2015 ChangJun High School, Inc. // I don't know what this program is. #include <iostream> #include <vector> #include <algorithm> #include <cstring> #include <cstdio> #include <cmath> using namespace std; typedef long long lol; int gi(){ int res=0,fh=1;char ch=getchar(); while((ch>'9'||ch<'0')&&ch!='-')ch=getchar(); if(ch=='-')fh=-1,ch=getchar(); while(ch>='0'&&ch<='9')res=res*10+ch-'0',ch=getchar(); return fh*res; } const int MAXN=110; const int INF=1e9; int d[MAXN][MAXN]; lol c[MAXN][MAXN]; int main(){ int n=gi(),m=gi(); for(int i=1;i<=n;i++) for(int j=1;j<=n;j++)d[i][j]=INF; for(int i=1;i<=m;i++){ int x=gi(),y=gi(); d[x][y]=d[y][x]=gi(); c[x][y]=c[y][x]=1; } for(int k=1;k<=n;k++) for(int i=1;i<=n;i++) for(int j=1;j<=n;j++){ if(d[i][k]+d[k][j]<d[i][j])d[i][j]=d[i][k]+d[k][j],c[i][j]=0; if(d[i][k]+d[k][j]==d[i][j])c[i][j]+=c[i][k]*c[k][j]; } for(int k=1;k<=n;k++){ double I=0; for(int i=1;i<=n;i++) for(int j=1;j<=n;j++){ if(k==i||k==j||i==j)continue; if(d[i][k]+d[k][j]!=d[i][j])continue; I+=double(c[i][k])*c[k][j]/c[i][j]; } printf("%.3lf\n",I); } return 0; } |
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