diff --git a/README.md b/README.md
index b1d352e..fe7dae5 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,4 @@
+# 算法笔记
 ## 线性动态规划优化为$O(n\log{n})$方法
 >如果是递增序列就lower_bound
 
diff --git a/src/8/28/P4342.cpp b/src/8/28/P4342.cpp
new file mode 100644
index 0000000..28170a4
--- /dev/null
+++ b/src/8/28/P4342.cpp
@@ -0,0 +1,31 @@
+/*
+
+dpmax[i][j]=编号[i,j]合并后的最大值
+dpmin[i][j]=编号[i,j]合并后的最小值
+
+if op[k] == +
+    dpmax[i][j]=max(dpmax[i][k]+dpmax[k+1][j])
+    dpmin[i][j]=min(dpmin[i][k]+dpmin[k+1][j])
+
+else if op[k] == *
+    dpmax[i][j]=max(dpmax[i][k]*dpmax[k+1][j],
+                    dpmax[i][k]*dpmin[k+1][j],
+                    dpmin[i][k]*dpmax[k+1][j],
+                    dpmin[i][k]*dpmin[k+1][j])
+
+    dpmin[i][j]=min(dpmax[i][k]*dpmax[k+1][j],
+                    dpmax[i][k]*dpmin[k+1][j],
+                    dpmin[i][k]*dpmax[k+1][j],
+                    dpmin[i][k]*dpmin[k+1][j])
+
+dpmax[i][j] = -1e9
+dpmin[i][j] =  1e9
+
+dp[i][i]=arr[i]
+
+*/
+
+
+int main(){
+
+}
\ No newline at end of file
diff --git a/src/8/28/opj8782.cpp b/src/8/28/opj8782.cpp
new file mode 100644
index 0000000..d0ffc25
--- /dev/null
+++ b/src/8/28/opj8782.cpp
@@ -0,0 +1,20 @@
+/*
+
+dp[i][j]=前i个数字添加j个乘号的最大值
+dp[i][j]=max(
+    dp[i][j],
+    dp[k][j-1] * num[k+1][i]
+)
+
+num[i][i]=n[i]-'0'
+num[i][j]=num[i][j-1]*10+(n[j]-'0')
+
+dp[i][j] = -1e9
+dp[i][0] = num[1][i]
+
+*/
+
+
+int main(){
+
+}