Submission #598464

#	Time	Username	Problem	Language	Result	Execution time	Memory
598464		MohamedFaresNebili	The Big Prize (IOI17_prize)	C++14	90 / 100	101 ms	1872 KiB

prize

#include <bits/stdc++.h>
#include "prize.h"
/// #pragma GCC optimize ("Ofast")
/// #pragma GCC target ("avx2")
/// #pragma GCC optimize("unroll-loops")
 
                using namespace std;
 
                using ll = long long;
                using ld = long double;
                using ii = pair<ll, ll>;
                using vi = vector<int>;
 
                #define ff first
                #define ss second
                #define pb push_back
                #define all(x) (x).begin(), (x).end()
                #define lb lower_bound
 
                const int MOD = 1e9 + 7;
 
                int A[200005][2];
                int curr = 0, calc = 0, res = -1;
 
                vector<int> query(int k) {
                    if(A[k][0] != -1)
                        return {A[k][0], A[k][1]};
                  	vector<int> V = ask(k);
                  	A[k][0] = V[0];
                  	A[k][1] = V[1];
                    return V;
                }
                void solve(int l, int r) {
                  	if(res != -1) return;
                  	vector<int> V = ask(r);
                  	if(V[0] + V[1] == curr && V[0] == calc)
                      return;
                  	if(l == r) {
                      calc++;
                      if(V[0] + V[1] == 0) 
                        res = l;
                      return;
                    }
                  int md = (l + r) / 2;
                  	solve(l, md); solve(md + 1, r);
                }
 
                int find_best(int N) {
                    memset(A, -1, sizeof A); int i = 0;
                    for(int l = 0; l < min(N, 500); l++) {
                      	int j = rand() % N;
                      	while(A[j][0] != -1) j = rand() % N;
                        vector<int> V = query(j);
                     	if(V[0] + V[1] == 0) return j;
                        curr = max(curr, V[0] + V[1]);
                    }
                    solve(0, N - 1);
                    return res;
                }

Compilation message (stderr)

prize.cpp: In function 'std::vector<int> query(int)':
prize.cpp:26:21: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   26 |                     if(A[k][0] != -1)
      |                     ^~
prize.cpp:28:20: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   28 |                    vector<int> V = ask(k);
      |                    ^~~~~~
prize.cpp: In function 'int find_best(int)':
prize.cpp:49:50: warning: unused variable 'i' [-Wunused-variable]
   49 |                     memset(A, -1, sizeof A); int i = 0;
      |                                                  ^

• Subtask 1: 20 / 20
• Subtask 2: 70 / 80