Add 13871.cpp

13xxx/13871.cpp

@@ -0,0 +1,26 @@
+#include <iostream>
+#include <vector>
+using namespace std;
+
+void solve(void) {
+  int n, c, s; cin >> n >> c >> s;
+  vector<int> x(c);
+  for (int i=0; i<c; i++) cin >> x[i];
+
+  int ans = (s == 1), cur = 1;
+  for (int i=0; i<c; i++) {
+    cur += x[i];
+    if (cur > n) cur = 1;
+    if (cur < 1) cur = n;
+    if (cur == s) ans++;
+  }
+  cout << ans;
+}
+
+int main(void) {
+  ios::sync_with_stdio(false);
+  cin.tie(nullptr);
+
+  solve();
+  return 0;
+}