Poj2377--bad cowtractors

The main topic: Bessie to destroy the FJ plan, to make a maximum spanning tree.

Analysis: Just change a symbol of the minimum spanning tree algorithm. In addition, to determine whether the graph is connected

Code

#include <cstdio> #include <cstring> #include <algorithm> using namespace std;

const int MAXN = 20010;
    struct edge{int S, E, W;
    BOOL operator < (const Edge & E1) const {return w > e1.w;
}}E[MAXN];
int f[1010], n, m;

int ans;
    int getfather (int x) {if (f[x] = = x) return x;
else return f[x] = Getfather (f[x]);
    } int kruscal () {sort (e+1, e+m+1);
    int cnt = n;
    for (int i = 1; I <= n; i++) f[i] = i;
        for (int i = 1; I <= m; i++) {int f1 = Getfather (E[I].S);
        int F2 = Getfather (E[I].E);
            if (f1! = F2) {F[F1] = F2;
            Ans + = E[I].W;
        cnt--;   }} if (cnt = = 1) return true;
CNT representative; The number of the Unicom block else return false; } int main () {while (~scanf ("%d%d", &n, &m)) {for (int i = 1; I <= m; i++) scanf ("%d%d
        %d ", &e[i].s, &AMP;E[I].E, &AMP;E[I].W);
        if (kruscal ()) printf ("%d\n", ans); else PrinTF (" -1\n");
} return 0;
 }