diff --git a/src/P2758/P2758.cpp b/src/P2758/P2758.cpp
new file mode 100644
index 0000000..fec42c8
--- /dev/null
+++ b/src/P2758/P2758.cpp
@@ -0,0 +1,44 @@
+#include <algorithm>
+#include <bits/stdc++.h>
+#include <limits>
+
+using ll = long long;
+
+auto &is = std::cin;auto &os = std::cout;
+
+const ll max_n {2000+5}, ll_max{std::numeric_limits<decltype(ll_max)>::max()};
+ll dp[max_n][max_n]{};
+std::string a,b;
+
+/*
+    dp[i][j]是前i个字符转化为j需要的最短编辑距离
+*/
+
+int main(){
+    is>>a>>b;
+    const ll a_size{(ll)a.size()}, b_size{(ll)b.size()};
+    a=' '+a,b=' '+b;
+    // for(ll i{0};i<max_n;i++)
+    //     for(ll j{0};j<max_n;j++)
+    //         dp[i][j]=ll_max;
+
+    for(ll i{0};i<std::max({a.size(),b.size()});i++){
+        dp[0][i]=i;
+        dp[i][0]=i;
+    }
+
+    for(ll i{1};i<=a_size;i++){
+        for(ll j{1};j<=b_size;j++){
+            if(a[i]==b[j]){
+                dp[i][j]=dp[i-1][j-1];
+            }else{
+                dp[i][j] = std::min({
+                    dp[i-1][j]+1, //删除
+                    dp[i][j-1]+1, //增加
+                    dp[i-1][j-1]+1//修改
+                });
+            }
+        }
+    }
+    os<<dp[a_size][b_size]<<'\n';
+}
\ No newline at end of file
diff --git a/src/P2758/P2758.py b/src/P2758/P2758.py
new file mode 100644
index 0000000..385afd4
--- /dev/null
+++ b/src/P2758/P2758.py
@@ -0,0 +1,23 @@
+max_n:int = 2000+5
+
+a:str='\0'+input().strip()
+b:str='\0'+input().strip()
+
+dp:list[list[int]] = [[max_n]*(len(b)+1) for _ in range(len(a)+1)]
+
+# print(dp)
+
+for i in range(0,len(a)+1):
+    dp[i][0]=i
+
+for i in range(0,len(b)+1):
+    dp[0][i]=i
+
+for i in range(1,len(a)):
+    for j in range(1,len(b)):
+        if a[i]==b[j]:
+            dp[i][j] = dp[i-1][j-1]
+            continue
+        dp[i][j]=min(dp[i-1][j],dp[i][j-1],dp[i-1][j-1])+1
+
+print(dp[len(a)-1][len(b)-1])
\ No newline at end of file
diff --git a/src/P5424/P5424.cpp b/src/P5424/P5424.cpp
index e69de29..a9b8f0b 100644
--- a/src/P5424/P5424.cpp
+++ b/src/P5424/P5424.cpp
@@ -0,0 +1,49 @@
+#include <bits/stdc++.h>
+#include <limits>
+// using namespace std;
+
+using ll = long long;
+
+const ll max_n = 400+5;
+ll n,k;
+ll a[max_n];
+ll dp[max_n][max_n], waste[max_n][max_n];
+/*
+抓住所有蛇的总浪费空间最小值
+dp[i][j] 抓住第i条蛇，使用了j次调整大小的浪费空间的最小值
+i,j,k
+    k分为两段，1~k,k+1~i
+    dp[i][j] = min(dp[i][j], dp[k][j-1]+waste[k+1][i])
+waste[i][j] 从i~j浪费的数量
+*/
+const ll ll_max{std::numeric_limits<ll>::max()};
+
+int main(){
+    std::cin>>n>>k;
+    for(ll i{1};i<=n;i++)std::cin>>a[i];
+    for(ll i{0};i<max_n;i++)
+        for(ll j{0};j<max_n;j++)
+            dp[i][j]=ll_max;
+    for(ll i{1};i<n;i++){
+        ll max_ai{a[i]},sum{a[i]};
+        // std::cout<<waste[i][i]<<' ';
+        for(ll j{i+1};j<=n;j++){
+            max_ai=std::max(a[j],max_ai);
+            sum+=a[j];
+            waste[i][j] = max_ai*(j-i+1)-sum;
+            // std::cout<<waste[i][j]<<' ';
+        }
+        dp[i][0] = waste[1][i];
+        // std::cout<<'\n';
+    }
+    
+    for(ll j{1};j<=k;j++){
+        for(ll i{j};i<=n;i++){
+            for(ll k{1};k<i;k++){
+                if(dp[k][j-1]==ll_max)continue;
+                dp[i][j] = std::min(dp[i][j], dp[k][j-1]+waste[k+1][i]);
+            }
+        }
+    }
+    std::cout<<dp[n][k]<<'\n';
+}
\ No newline at end of file
diff --git a/src/oj1808/oj1808.cpp b/src/oj1808/oj1808.cpp
new file mode 100644
index 0000000..4775d2b
--- /dev/null
+++ b/src/oj1808/oj1808.cpp
@@ -0,0 +1,31 @@
+
+#include <algorithm>
+#include <iostream>
+#include <string>
+
+using ll = long long;
+
+auto &is = std::cin;
+auto &os = std::cout;
+
+const ll max_n{200+5};
+std::string a,b;
+ll dp[max_n][max_n];
+
+int main(){
+    while (is>>a>>b) {
+        a=' '+a;
+        b=' '+b;
+
+        for(ll i{1};i<a.size();i++){
+            for(ll j{1};j<b.size();j++){
+                if(a[i]==b[j]){
+                    dp[i][j]=dp[i-1][j-1]+1;
+                }else{
+                    dp[i][j]=std::max({dp[i][j-1],dp[i-1][j]});
+                }
+            }
+        }
+        os<<dp[a.size()-1][b.size()-1]<<'\n';
+    }
+}
\ No newline at end of file
diff --git a/src/oj1808/oj1808.py b/src/oj1808/oj1808.py
new file mode 100644
index 0000000..cf4c361
--- /dev/null
+++ b/src/oj1808/oj1808.py
@@ -0,0 +1,25 @@
+import re
+from typing import List
+
+
+max_n = 200+5
+
+dp:List[List[int]] = [[0]*max_n for _ in range(max_n)]
+
+while True:
+    try:
+        raw_str = input().strip()
+        a, b = map(lambda x:" "+x, re.split(r"\s+",raw_str,maxsplit=1))
+    except EOFError:
+        break
+
+    for i in range(1,len(a)):
+        for j in range(1,len(b)):
+            if a[i] == b[j]:
+                # print(i,j,"ok")
+                dp[i][j] = dp[i-1][j-1] + 1
+            else:
+                dp[i][j] = max(dp[i-1][j], dp[i][j-1])
+    
+    # print(dp,repr(a),repr(b))
+    print(dp[len(a)-1][len(b)-1])
\ No newline at end of file