#181. Alice&时间隧道

https://sjzezoj.com/submission/48560

S2OJ/181/181.cpp

@@ -0,0 +1,27 @@
+#include <algorithm>
+#include <iostream>
+
+using std::cin;
+using std::cout;
+#define endl '\n'
+
+const int N = 200005;
+
+int n, a[N], ans;
+
+int main() {
+    cin >> n;
+    for (int i = 1; i <= n; i++) {
+        cin >> a[i];
+    }
+    std::sort(a + 1, a + 1 + n);
+    n = std::unique(a + 1, a + 1 + n) - a - 1;
+    a[n + 1] = std::numeric_limits<int>::max();
+    for (int i = 1; i <= n; i++) {
+        for (int j = 2; (j - 1) * a[i] <= a[n]; j++) {
+            ans = std::max(ans, *(std::lower_bound(a + 1, a + 1 + n + 1, j * a[i]) - 1) % a[i]);
+        }
+    }
+    cout << ans << endl;
+    return 0;
+}