Submission #95223

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
95223	2019-01-28T17:08:36 Z	MvC	The Big Prize (IOI17_prize)	C++11	Compilation error	0 ms	0 KB

prize

#include "prize.h"
#include<bits/stdc++.h>
#include <vector>
#include <algorithm>
#include <set>
using namespace std;
 
int m, res;
bool flag = false;
vector<int> mem[200005];
 
vector<int> qr(int x){
    if(mem[x].size() == 0) mem[x] = ask(x);
    return mem[x];
}
 
void solve(int l, int r, int num, int bef){
    if(num == 0) return;
    if(l > r) return;
    int mid = (l+r)/2;
    vector<int> resp = qr(mid);
    if(resp[0]+resp[1] == 0){
        res = mid;
        flag = true;
        return;
    }
    int b = mid;
    while(resp[0]+resp[1] != m && b < r){
        b++;
        resp = qr(b);
        if(resp[0]+resp[1] == 0){
            res = b;
            flag = true;
            return;
        }
    }
    if(resp[0]+resp[1] == m){
        solve(b+1, r, num-(resp[0]-bef), resp[0]);
        if(flag) return;
        solve(l, mid-1, resp[0]-(b-mid)-bef, bef);
        if(flag) return;
    } else{
        solve(l, mid-1, num, bef);
    }
    return;
}
 
int find_best(int n) {
  srand(time(0));
    if(n <= 5000){
        for(int i=0; i<n; i++){
            vector<int> resp = qr(i);
            if(resp[0]+resp[1] == 0) return i;
        }
    }
    vector<int> resp;
    set<int> s;
  vector<int>vc;
  set<int>ss;
  for(int i=0;i<n;i++)ss.insert(i);
  int x=0;
    for(x<600){
        int i = rand()%n;
      if(ss.find(i)!=ss.end())
      {
        x++;
        ss.erase(ss.find(i));
      }
      else continue;
        resp = qr(i);
        if(resp[0]+resp[1] == 0) return i;
        s.insert(resp[0]+resp[1]);
        m = max(m, resp[0]+resp[1]);
        if(s.size() == 4) break;
    }
    
    solve(0, n-1, m, 0);
    
    return res;
}

Compilation message

prize.cpp: In function 'int find_best(int)':
prize.cpp:62:14: error: expected ';' before ')' token
     for(x<600){
              ^
prize.cpp:62:10: warning: statement has no effect [-Wunused-value]
     for(x<600){
         ~^~~~
prize.cpp:77:10: error: could not convert 'solve(0, (n - 1), m, 0)' from 'void' to 'bool'
     solve(0, n-1, m, 0);
     ~~~~~^~~~~~~~~~~~~~
prize.cpp:79:5: error: expected primary-expression before 'return'
     return res;
     ^~~~~~
prize.cpp:79:5: error: expected ')' before 'return'