'commit'

TangDou/Topic/HuanGenDp/SubTree.cpp

@@ -17,11 +17,13 @@ int pro1[N], pro2[N];
 void dfs1(int u, int fa) {
     f[u] = 1;
     vector<int> 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;