feat: 添加两个算法题目解决方案

添加P10131.cpp和mn1009t2.cpp两个算法题目的解决方案代码。P10131.cpp解决相邻元素匹配问题，mn1009t2.cpp实现基于双端队列的优化算法。

src/10/10/P10131.cpp

@@ -0,0 +1,42 @@
+#include <cstdint>
+#include <iostream>
+#include <istream>
+#include <set>
+using ll = int64_t;
+#define sl static inline
+
+const ll maxn = 1e5+5;
+ll T,n,h[maxn];
+std::set<ll> s;
+
+sl void solve(){
+    std::cin>>n;
+    for(ll i=1;i<=n;i++)std::cin>>h[i];
+    s.clear();
+    for(ll i=2;i<=n;i++){
+        if(h[i-1]==h[i] && s.find(h[i])==s.end()){
+            s.insert(h[i]);
+        }
+    }
+    for(ll i=3;i<=n;i++){
+        if(h[i]==h[i-2] && s.find(h[i])==s.end()){
+            s.insert(h[i]);
+        }
+    }
+    if(s.empty()){
+        std::cout<<"-1\n";
+        return;
+    }
+    for(const ll i:s){
+        std::cout<<i<<" ";
+    }
+    std::cout<<"\n";
+}
+
+int main(){
+    std::iostream::sync_with_stdio(false);
+    std::cin.tie(nullptr);
+
+    std::cin>>T;
+    while(T--)solve();
+}

src/10/10/mn1009t2.cpp

@@ -0,0 +1,41 @@
+#include <cstdint>
+#include <deque>
+#include <iostream>
+#include <istream>
+#include <utility>
+using ll = int64_t;
+
+const ll maxn = 2e6+5;
+ll n,m,v,d[maxn],p[maxn],ans=0;
+std::deque<std::pair<ll, ll>> dq; // 价钱，剩余
+
+int main(){
+    std::iostream::sync_with_stdio(false);
+    std::cin.tie(nullptr);
+
+    std::cin>>n>>m>>v;
+    for(ll i=1;i<=n;i++)std::cin>>d[i];
+    for(ll i=1;i<=n;i++)std::cin>>p[i];
+
+    for(ll i=1;i<=n;i++){
+        const ll jdnp = p[i]-m*i;
+        while(dq.size() && dq.back().first >= jdnp)dq.pop_back();
+        dq.emplace_back(jdnp, d[i]+v);
+        while(d[i]){
+            if(dq.front().second > d[i]){
+                ans+=(dq.front().first+i*m)*d[i];
+                d[i]=0;
+            }else if(dq.front().second == d[i]){
+                ans+=(dq.front().first+i*m)*d[i];
+                d[i]=0;
+                dq.pop_front();
+            }else{
+                ans+=(dq.front().first+i*m)*dq.front().second;
+                d[i]-=dq.front().second;
+                dq.pop_front();
+            }
+        }
+        dq.back().second=v;
+    }
+    std::cout<<ans<<"\n"; //DEBUGGING
+}