'commit'

TangDou/Topic/Mobius/P4318.cpp

@@ -28,26 +28,26 @@ void get_mobius(int n) {
     // 维护u(x)前缀和:梅滕斯函数
     for (int i = 1; i <= n; i++) sum[i] = sum[i - 1] + mu[i];
 }
-int check(int g) {
+int check(int g, int k) {
     int res = 0;
     for (int i = 1; i * i <= g; i++)
         res = res + mu[i] * (g / i / i);
 
-    return res;
+    return res >= k;
 }
 
 signed main() {
+    // 获取莫比乌斯函数值
     get_mobius(N - 1);
 
-    int t, k;
-    cin >> t;
-    while (t--) {
-        cin >> k;
-        int l = 1, r = 2e9, mid, vt;
+    int T, k;
+    cin >> T; // T组测试数据
+    while (T--) {
+        cin >> k; // 第k个数
+        int l = 1, r = 2e9;
         while (l <= r) {
-            mid = (l + r) / 2;
-            vt = check(mid);
-            if (vt < k)
+            int mid = l + r >> 1;
+            if (!check(mid, k))
                 l = mid + 1;
             else
                 r = mid - 1;