diff --git a/TangDou/Topic/HuanGenDp/SubTree.cpp b/TangDou/Topic/HuanGenDp/SubTree.cpp index a4e394f..613765f 100644 --- a/TangDou/Topic/HuanGenDp/SubTree.cpp +++ b/TangDou/Topic/HuanGenDp/SubTree.cpp @@ -17,11 +17,13 @@ int pro1[N], pro2[N]; void dfs1(int u, int fa) { f[u] = 1; vector edgeson; + for (int i = h[u]; ~i; i = ne[i]) { int v = e[i]; if (v == fa) continue; dfs1(v, u); - f[u] = 1LL * f[u] * (f[v] + 1) % mod; + + f[u] = f[u] * (f[v] + 1) % mod; edgeson.push_back(v); // 将子节点加入集合,方便之后操作 } int pre1 = 1; @@ -29,12 +31,12 @@ void dfs1(int u, int fa) { for (int i = 0; i < edgeson.size(); i++) { pro1[edgeson[i]] = pre1; - pre1 = 1LL * pre1 * (f[edgeson[i]] + 1) % mod; + pre1 = pre1 * (f[edgeson[i]] + 1) % mod; } // 预处理前缀积 for (int i = edgeson.size() - 1; i >= 0; i--) { pro2[edgeson[i]] = pre2; - pre2 = 1LL * pre2 * (f[edgeson[i]] + 1) % mod; + pre2 = pre2 * (f[edgeson[i]] + 1) % mod; } // 预处理后缀积 } @@ -42,7 +44,8 @@ void dfs2(int u, int fa) { if (fa == 0) g[u] = 1; // 特判根节点 else - g[u] = (g[fa] * (1LL * pro1[u] * pro2[u] % mod) % mod + 1) % mod; + g[u] = (g[fa] * (pro1[u] * pro2[u] % mod) % mod + 1) % mod; + for (int i = h[u]; ~i; i = ne[i]) { int v = e[i]; if (v == fa) continue;