Submission #77371

#	Time	Username	Problem	Language	Result	Execution time	Memory
77371		xiaowuc1	Brunhilda’s Birthday (BOI13_brunhilda)	C++14	100 / 100	69 ms	39564 KiB

brunhilda

#include <bits/stdc++.h>

/*
unsigned seed1 = std::chrono::system_clock::now().time_since_epoch().count();
mt19937 g1.seed(seed1);

ios_base::sync_with_stdio(false);
cin.tie(NULL);
*/
using namespace std;

const double PI = 2 * acos(0);

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef long double ld;
typedef vector<vector<ll>> matrix;

int primes[100000];
int thresh[10000000];

int main() {
  int n;
  int q;
  scanf("%d%d", &n, &q);
  for(int i = n-1; i >= 0; i--) {
    scanf("%d", &primes[i]);
  }
  thresh[1] = primes[0]-1;
  int ans = 2;
  while(thresh[ans-1] <= 10000000) {
    int last = thresh[ans-1];
    int best = last;
    for(int i = 0; i < n; i++) {
      if((last+1)%primes[i] == 0) continue;
      int t = last - (last) % primes[i] + primes[i] - 1;
      if(t > best) {
        best = t;
      }
      if(last + primes[i] - 1 <= best) break;
    }
    if(last == best) break;
    thresh[ans++] = best;
    last = best;
  }
  ans--;
  while(q--) {
    int goal;
    scanf("%d", &goal);
    if(goal > thresh[ans]) {
      printf("oo\n");
    }
    else {
      int lhs = 1;
      int rhs = ans;
      while(lhs != rhs) {
        int mid = (lhs+rhs)/2;
        if(thresh[mid] < goal) lhs = mid+1;
        else rhs = mid;
      }
      printf("%d\n", lhs);
    }
  }
}

Compilation message (stderr)

brunhilda.cpp: In function 'int main()':
brunhilda.cpp:27:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d", &n, &q);
   ~~~~~^~~~~~~~~~~~~~~~
brunhilda.cpp:29:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &primes[i]);
     ~~~~~^~~~~~~~~~~~~~~~~~
brunhilda.cpp:51:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &goal);
     ~~~~~^~~~~~~~~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 20 / 20
• Subtask 3: 60 / 60