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//这个程序能得90分，其中第九组数据应该输出55，但这个程序输出56，不知道为什么。
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#include <cstdio>
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#include <cstring>
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int n, p, maxd;
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int w[400];
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typedef struct Edge
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{
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int from, to;
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Edge *next;
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Edge(int f, int t, Edge *n = 0) : from(f), to(t), next(n) {}
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} * lpEdge;
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#define addEdge(Gp, x, y) (Gp)[x] = new Edge((x), (y), (Gp)[x]);
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lpEdge G1[302], G[302], Dep[302];
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bool vis[302];
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void build(int id)
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{
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vis[id] = true;
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for (lpEdge cur = G1[id]; cur; cur = cur->next)
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if (!vis[cur->to])
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{
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addEdge(G, id, cur->to);
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build(cur->to);
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}
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}
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int getWeight(int id)
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{
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if (~w[id])
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return w[id];
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else
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{
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int cnt = 1;
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for (lpEdge cur = G[id]; cur; cur = cur->next)
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cnt += getWeight(cur->to);
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return w[id] = cnt;
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}
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}
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void getDepth(int id, int d)
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{
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if (id > maxd) maxd = id;
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addEdge(Dep, d, id);
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for (lpEdge cur = G[id]; cur; cur = cur->next)
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getDepth(cur->to, d + 1);
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}
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void setSafe(int id)
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{
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vis[id] = true;
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for (lpEdge cur = G[id]; cur; cur = cur->next)
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setSafe(cur->to);
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}
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int main()
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{
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memset(w, -1, sizeof(w));
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scanf("%d%d", &n, &p);
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for (int i = 0, a, b; i < p; i++)
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{
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scanf("%d%d", &a, &b);
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addEdge(G1, a, b);
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addEdge(G1, b, a);
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}
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build(1);
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getWeight(1);
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getDepth(1, 0);
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memset(vis, 0, sizeof(vis));
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int safeCnt = 0;
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for (int i = 1, maxn, maxid; i <= maxd; i++)
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{
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maxn = maxid = 0;
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for (lpEdge cur = Dep[i]; cur; cur = cur->next)
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if (!vis[cur->to] && w[cur->to] > maxn) maxn = w[maxid = cur->to];
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safeCnt += maxn;
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setSafe(maxid);
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}
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printf("%d", n - safeCnt);
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return 0;
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}
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