'commit'

TangDou/CSP-J/AcWingTraining/T4/441.cpp

@@ -0,0 +1,19 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+const int N = 10010;
+
+int main() {
+    int l, r;
+    cin >> l >> r;
+
+    int res = 0;
+    for (int i = l; i <= r; i++)
+        for (int j = i; j; j /= 10)
+            if (j % 10 == 2)
+                res++;
+
+    cout << res << endl;
+
+    return 0;
+}