new file: P16060.cpp

P16060.cpp

@@ -0,0 +1,31 @@
+#include <bits/stdc++.h>
+using namespace std;
+int n, N;
+map<int, int> changes;
+int main() {
+    scanf("%d%d", &n, &N);
+    for (int i = 1, a; i <= n; ++i)
+        scanf("%d", &a), changes[a] = 1;
+    for (int i = 1; i * (N / (n + 1)) < N; i++) {
+        if (changes.find(i * (N / (n + 1))) != changes.end())
+            changes[i * (N / (n + 1))] = 3;
+        else
+            changes[i * (N / (n + 1))] = 2;
+    }
+    changes[N] = 2;
+    int nowf = 0, nowg = 0;
+    long long ans = 0;
+    pair<int, int> pre = {0, 0};
+    for (pair<int, int> now : changes) {
+        ans += abs(nowg - nowf) * (now.first - pre.first);
+        if (now.second == 1)
+            nowf++;
+        else if (now.second == 2)
+            nowg++;
+        else
+            nowf++, nowg++;
+        pre = now;
+    }
+    printf("%lld\n", ans);
+    return 0;
+}