'commit'

TangDou/Topic/HuanGenDp/P3047.cpp

@@ -1,75 +1,60 @@
 #include <bits/stdc++.h>
-#define re register
-typedef long long ll;
 using namespace std;
-inline ll read() {
+#define int long long
-    ll a = 0, f = 1;
+#define endl "\n"
-    char c = getchar();
+
-    while (c < '0' || c > '9') {
+int n, q;
-        if (c == '-') f = -1;
+int head[200010], dp[200010][21];
-        c = getchar();
-    }
-    while (c >= '0' && c <= '9') {
-        a = a * 10 + c - '0';
-        c = getchar();
-    }
-    return a * f;
-} // 好用的快读
-ll n, q;
-ll head[200010], dp[200010][21];
 struct ljj {
-    ll to, stb;
+    int to, stb;
 } a[200010];
-ll s = 0;
+int s = 0;
-inline void insert(ll x, ll y) {
+inline void insert(int x, int y) {
     s++;
     a[s].stb = head[x];
     a[s].to = y;
     head[x] = s;
 }
-inline void dfs(ll x, ll fa) {
+inline void dfs(int x, int fa) {
-    for (re ll i = head[x]; i; i = a[i].stb) {
+    for (int i = head[x]; i; i = a[i].stb) {
-        ll xx = a[i].to;
+        int xx = a[i].to;
         if (xx == fa)
             continue;
         dfs(xx, x);
-        for (re ll j = 1; j <= q; j++)
+        for (int j = 1; j <= q; j++)
             dp[x][j] += dp[xx][j - 1]; // 第一遍dp
     }
 }
-inline void dfs1(ll x, ll fa) {
+inline void dfs1(int x, int fa) {
-    for (re ll i = head[x]; i; i = a[i].stb) {
+    for (int i = head[x]; i; i = a[i].stb) {
-        ll xx = a[i].to;
+        int xx = a[i].to;
-        if (xx == fa)
+        if (xx == fa) continue;
-            continue;
         // 在第一次遍历时 dp[1][2] 包括了 dp[2][1] 2的子树权值；
         // 然鹅  ans在统计dp[2][3] 的时候也加上了 dp[2][1]  2的子树权值；
         // 第二次遍历 dp[2][3] 又加上了 dp[2][1];
         // 所以需要简单容斥一下；
-        for (re ll j = q; j >= 2; j--)
+        for (int j = q; j >= 2; j--)
             dp[xx][j] -= dp[xx][j - 2]; // 简单容斥
-        for (re ll j = 1; j <= q; j++)
+        for (int j = 1; j <= q; j++)
             dp[xx][j] += dp[x][j - 1]; // 第二遍dp
         dfs1(xx, x);
     }
 }
-int main() {
+signed main() {
-    n = read();
+    cin >> n >> q;
-    q = read();
+    for (int i = 1; i < n; i++) {
-    for (re ll i = 1; i < n; i++) {
+        int x, y;
-        ll x = read(), y = read();
+        cin >> x >> y;
         insert(x, y);
         insert(y, x);
     }
-    for (re ll i = 1; i <= n; i++)
+    for (int i = 1; i <= n; i++) cin >> dp[i][0]; // 每个节点往外0距离，就是它本身的权值；
-        dp[i][0] = read(); // 每个节点往外0距离，就是它本身的权值；
     dfs(1, 0);
     dfs1(1, 0);
-    for (re ll i = 1; i <= n; i++) {
+
-        ll ans = 0;
+    for (int i = 1; i <= n; i++) {
-        for (re ll j = 0; j <= q; j++)
+        int ans = 0;
-            ans += dp[i][j]; // ans统计答案
+        for (int j = 0; j <= q; j++) ans += dp[i][j]; // ans统计答案
         printf("%lld\n", ans);
     }
-    return 0;
 }