From 5f7301d876f9268154c9728386a1e6cdd017201c Mon Sep 17 00:00:00 2001
From: Zengtudor <Zengtudor@outlook.com>
Date: Tue, 22 Jul 2025 15:25:27 +0800
Subject: [PATCH] update

---
 .gitignore         |  3 ++-
 src/7/22/P1282.cpp | 45 +++++++++++++++++++++++++--------------------
 2 files changed, 27 insertions(+), 21 deletions(-)

diff --git a/.gitignore b/.gitignore
index e050ba0..79e6206 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 /build
-/.cache
\ No newline at end of file
+/.cache
+/test.*
\ No newline at end of file
diff --git a/src/7/22/P1282.cpp b/src/7/22/P1282.cpp
index 91fa5de..75f8f21 100644
--- a/src/7/22/P1282.cpp
+++ b/src/7/22/P1282.cpp
@@ -3,26 +3,24 @@
 #include <cstdlib>
 #include <iostream>
 #include <istream>
+#include <limits>
 #include <vector>
 
 using ll = int64_t;
 
-ll n,a,b;
+ll n,a,b,ans=std::numeric_limits<ll>::max();
 std::vector<std::vector<ll>> dp;
+constexpr ll idxa = 6000+7;
 
 template<class ...Ts>
-void log(Ts&&...ts){
+static inline __attribute__((always_inline)) void log(Ts&&...ts){
     std::cout<<"Log: ";
     ((std::cout<<ts<<' '),...);
     std::cout<<'\n';
 }
 
-void pdp(){
-    std::cout<<"{";
-    for(ll i=0;i<dp.size();i++){
-        std::cout<<"{"<<dp[i][0]<<","<<dp[i][1]<<"}, ";
-    }
-    std::cout<<"}\n";
+static inline __attribute__((always_inline)) ll& getdp(ll i,ll j){
+    return dp[i%2][j+idxa];
 }
 
 int main(){
@@ -31,23 +29,30 @@ int main(){
     std::cout.tie(nullptr);
 
     std::cin>>n;
-    dp.resize(n+1,std::vector<ll>(2));
+    dp.resize(2,std::vector<ll>(2*idxa+1,std::numeric_limits<ll>::max()-7));
+    getdp(0, 0)=0;
     for(ll i=1;i<=n;i++){
         /*
-            dp[k][0]    dp[k][1]
+            i=前i个 <=1000
+            j=当前的差值  -6000<=j<=6000
+            k为最小翻转次数 <=1000
+            dp[i][j]=k
+            O(1000*12000)=1e7
         */
         std::cin>>a>>b;
-        if(abs(dp[i-1][0]+a-b)<abs(dp[i-1][1]+a-b)){
-            dp[i][0]=dp[i-1][0]+a-b;
-        }else{
-            dp[i][0]=dp[i-1][1]+a-b;
+        for(ll j=6000;j>=-6000;j--){
+            getdp(i, j)=std::min(getdp(i, j),getdp(i-1, j-(a-b)));
+            getdp(i, j)=std::min(getdp(i, j),getdp(i-1, j-(-a+b))+1);
         }
-        if(abs(dp[i-1][0]+b-a)<abs(dp[i-1][1]+b-a)){
-            dp[i][1]=dp[i-1][0]+b-a;
-        }else{
-            dp[i][1]=dp[i-1][1]+b-a;
+        dp[i%2==1?0:1].assign(2*idxa+1,std::numeric_limits<ll>::max()-7);
+    }
+    for(ll i=0;i<=6000;i++){
+        if(getdp(n, i)<=1000){
+            std::cout<<getdp(n, i)<<'\n';
+            break;
+        }else if(getdp(n, -i)<=1000){
+            std::cout<<getdp(n, -i)<<'\n';
+            break;
         }
     }
-    pdp();
-    std::cout<<std::min(abs(dp[n][0]),abs(dp[n][1]))<<'\n';
 }
\ No newline at end of file