new file: B3805.cpp [skip ci]

B3805.cpp

@@ -0,0 +1,14 @@
+#include <bits/stdc++.h>
+using namespace std;
+int n, s;
+int main() {
+    scanf("%d", &n);
+    int ans = 0;
+    for (int i = 1; i <= n; ++i) {
+        scanf("%d", &s);
+        if (s == i)
+            ans++;
+    }
+    printf("%d\n", ans);
+    return 0;
+}