//------------Floyd--------------int map[N][N];void Floyd(int n){ int i,j,k; for(k=1;k<=n;k++) for(i=1;i<=n;i++) for(j=1;j<=n;j++) if(map[i][k]+map[k][j]<map[i][j]) map[i][j]=map[i][k]+map[k][j];}///最好写了!