diff --git a/AtCoder/ABC251/C/C.cpp b/AtCoder/ABC251/C/C.cpp
new file mode 100644
index 00000000..81605ed2
--- /dev/null
+++ b/AtCoder/ABC251/C/C.cpp
@@ -0,0 +1,33 @@
+#include <iostream>
+#include <string>
+#include <unordered_map>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+int n;
+std::string s;
+std::unordered_map<std::string, bool> map;
+std::pair<int, int> ans;
+
+int main() {
+    std::ios::sync_with_stdio(false);
+
+    cin >> n;
+
+    for (int i = 1, x; i <= n; i++) {
+        cin >> s >> x;
+
+        if (!map.count(s)) {
+            map[s] = true;
+            if (x > ans.first) {
+                ans = std::make_pair(x, i);
+            }
+        }
+    }
+
+    cout << ans.second << endl;
+
+    return 0;
+}