diff --git a/src/cpp/total-appeal-of-a-string.cpp b/src/cpp/total-appeal-of-a-string.cpp
new file mode 100644
index 0000000..abe02a9
--- /dev/null
+++ b/src/cpp/total-appeal-of-a-string.cpp
@@ -0,0 +1,26 @@
+// https://leetcode.com/problems/total-appeal-of-a-string/
+class Solution {
+public:
+    typedef long long ll;
+    long long appealSum(string s) {
+        ll ans=0;
+        ll n=s.size();
+        for(char a='a';a<='z';a++){
+          vector<int> idx;
+            idx.push_back(-1);
+            for(int i=0;i<n;i++){
+                if(s[i]==a)idx.push_back(i);
+            }
+            idx.push_back(n);
+            ll sans=n*(n+1)/2LL;      // all substrings of binary string
+            if(idx.empty())continue;
+            for(int i=1;i<idx.size();i++){
+                ll x=idx[i-1]+1,y=idx[i]-1;
+                ll z=y-x+1;                           // strings of format 1 "0000" 1 being subtracted
+                sans-=z*(z+1)/2;
+            }
+            ans+=sans;
+        }
+        return ans;
+    }
+};