UVA 10859 Placing Lampposts——dp

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#include    <cstdio>
#include    <vector>
#include   <cstring>
#include  <iostream>
#include <algorithm>
using namespace std;
const int maxn = 1010;
int T, n, m;
bool vis[maxn];
int dp[maxn][2], f[maxn][2];
vector<int> G[maxn];
void init() {
    for (int i = 0; i < n; i++) G[i].clear();
    for (int i = 0; i < n; i++) vis[i] = 0;
}
void dfs(int u) {
    dp[u][1] = 1, dp[u][0] = 0;
    f[u][1] = 0, f[u][0] = 0;
    for (int i = 0; i < G[u].size(); i++) {
        int v = G[u][i];
        if (vis[v]) continue;
        vis[v] = 1;
        dfs(v);
        dp[u][0] += dp[v][1];
        f[u][0] += f[v][1];
        if (dp[v][0] < dp[v][1]) {
            dp[u][1] += dp[v][0];
            f[u][1] += f[v][0];
        }
        else if (dp[v][0] > dp[v][1]) {
            dp[u][1] += dp[v][1];
            f[u][1] += f[v][1]+1;
        }
        else {
            dp[u][1] += dp[v][0];
            f[u][1] += max(f[v][0], f[v][1] + 1);
        }
    }
}
int main() {
    scanf("%d", &T);
    while (T--) {
        scanf("%d%d", &n, &m);
        init();
        int u, v;
        for (int i = 0; i < m; i++) {
            scanf("%d%d", &u, &v);
            G[u].push_back(v);
            G[v].push_back(u);
        }
        int ans1 = 0, ans2 = 0;
        for (int i = 0; i < n; i++) {
            if (vis[i]) continue;
            vis[i] = 1;
            dfs(i);
            int x = 0, y = 0;
            if (dp[i][0] < dp[i][1]) { x = dp[i][0], y = f[i][0]; }
            else if (dp[i][0] > dp[i][1]) { x = dp[i][1], y = f[i][1]; }
            else { x = dp[i][0]; y = max(f[i][0], f[i][1]); }
            ans1 += x, ans2 += y;
        }
        printf("%d %d %d\n", ans1, ans2, m - ans2);
    }
    return 0;
}