洛谷SCP 2024 第一轮（初赛 J 组）模拟题解析（第三部分：完善程序（1-2））

完善程序一（补全）

 #include <bits/stdc++.h>
 using namespace std;
 const int MAXN = 100000;
 int n;
 int vis[MAXN], a[MAXN];
 vector<int> ans;
 int check(int k) {
     int x = n, top = 0;
     for (int i = 0; i <= k; i++) vis[i] = 0;
     while ( x > 0  ) {
         a[++top] =  x % k   ;
         x = x / k;
     }
     if (top < 2)
     return 0;
     for (int i = 1; i <= top; i++) {
         if (vis[a[i]] == 1 )
         return 0;
         vis[a[i]] = 1;
     }
 return 1;
 }
 int main() {
     cin >> n;
     for (int i = 2; i <= n; i++) {
     if (check(i))
     ans.push_back(i);
     }
     if (ans.empty()) {
        cout << -1;
     }
     for (int i = 0; i < ans.size(); i++)
     cout << ans[i] << " ";
     return 0;
 }

完善程序二（补全）

  #include <bits/stdc++.h>
  using namespace std; 
  const int MAXW = 753005;
  const int days[13] = {0, 31, 0, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
  int prime[MAXW], cnt;
  bool not_prime[MAXW];


  void linear_prime(int n) { 
          --n;
          not_prime[0] = not_prime[1] = true;
          for(int i = 2; i <= n; i++) {
                   if(not_prime[i] == false)
                           prime[++cnt]=i;
                   for(int j = 1; (j <= cnt) && (i * prime[j] <= n); j++) {
                            not_prime[i * prime[j]] = 1;
                            if(i % prime[j] == 0) 
				            break;
                   }
           }
  }
  bool check(int n) {
           return (n % 400 == 0 || (n % 4== 0 && n % 100 != 0));   
		   }

  int main() {
          linear_prime(MAXW);
           int x, y, z, w;
           cin >> x >>y >> z;
           if(y == 2)
                    w = check(x) ? 29 : 28;
          else
                   w = days[y];
           if(not_prime[x * y * (w - z + 1)])
                   cout << "unlucky" << endl;
          else
                  cout << "lucky" << endl;
           return 0; 
  }