From f67a1ebcb3eff41c4c0b862b15cd206c407ef482 Mon Sep 17 00:00:00 2001
From: Zengtudor <zengtudor@outlook.com>
Date: Wed, 5 Nov 2025 18:37:07 +0800
Subject: [PATCH] =?UTF-8?q?fix(P3953):=20=E4=BF=AE=E5=A4=8DDFS=E9=80=BB?=
 =?UTF-8?q?=E8=BE=91=E9=94=99=E8=AF=AF=E5=B9=B6=E6=B7=BB=E5=8A=A0=E8=B0=83?=
 =?UTF-8?q?=E8=AF=95=E8=BE=93=E5=87=BA?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

修复DFS函数中节点1的处理逻辑，调整nk的比较运算符，并添加printf调试输出
优化solve函数中dp数组的初始化范围
---
 src/11/5/P3953.cpp | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/src/11/5/P3953.cpp b/src/11/5/P3953.cpp
index 2f2d900..5bb1c5c 100644
--- a/src/11/5/P3953.cpp
+++ b/src/11/5/P3953.cpp
@@ -7,7 +7,7 @@
 #include <vector>
 using ll = int64_t;
 #define sl static inline
-// #define printf
+#define printf
 const ll maxm=2e5+5,inf=1e9+7;
 ll n,m,k,p,nt,d[maxm],dp[maxm][57];
 bool isn,vis[maxm][57];
@@ -54,21 +54,28 @@ sl ll dfs(ll u,ll k){
         isn=true;
         return 0;
     }
-    if(u==1)return k==0?1:0;
-    vis[u][k]=true;
     if(dp[u][k]!=-1){
+        printf("dp[%lld][%lld]=%lld, in temp\n",u,k,dp[u][k]);
         return dp[u][k];
     }
+    vis[u][k]=true;
     ll nans=0;
     for(auto[v,w]:re[u]){
         ll nk=d[u]+k-d[v]-w;
-        if(nk<0||nk>k)continue;
+        if(nk<0||nk>::k)continue;
         nans=(nans+dfs(v, nk))%p;
         if(isn){
+            vis[u][k]=false;
             return 0;
         }
     }
+    if(u==1){
+        const ll ret= k==0?1:0;
+        printf("dp[%lld][%lld]=%lld u==1\n",u,k,ret);
+        nans=ret;
+    }
     vis[u][k]=false;
+    printf("dp[%lld][%lld]=%lld\n",u,k,nans);
     return dp[u][k]=nans;
 }
 
@@ -81,12 +88,11 @@ sl void solve(){
     re.clear();
     re.resize(n+1);
     for(ll i=1;i<=n;i++){
-        for(ll j=1;j<=50;j++){
+        for(ll j=0;j<=k;j++){
             dp[i][j]=-1;
             vis[i][j]=false;
         }
     }
-    dp[1][0]=1;
     for(ll i=1;i<=m;i++){
         ll u,v,w;
         std::cin>>u>>v>>w;
@@ -99,9 +105,10 @@ sl void solve(){
         std::cout<<"0\n";
         return;
     }
-    const ll ms=d+k;
+    // const ll ms=d+k;
     ll ans=0;
     for(ll i=0;i<=k;i++){
+        printf("DFS i=%lld----\n",i);
         ans=(ans+dfs(n,i))%p;
         if(isn){
             std::cout<<"-1\n";