Submission #1058138

#	Time	Username	Problem	Language	Result	Execution time	Memory
1058138		idas	Counting Mushrooms (IOI20_mushrooms)	C++17	0 / 100	0 ms	432 KiB

mushrooms

#include "mushrooms.h"
#include "bits/stdc++.h"
#define FOR(i, begin, end) for(int i=(begin); i<(end); i++)
#define sz(x) ((int)((x).size()))
#define pb push_back

using namespace std;
typedef vector<int> vi;

const int MxN=2e4, C=142;
int n;
vi a, b;

int count_mushrooms(int N) {
    n=N; a.pb(0);

    if(use_machine({0,1})) b.pb(1);
    else a.pb(1);

    if(use_machine({0,2})) b.pb(2);
    else a.pb(2);

    int in=3;
    while(in<=n-2 && sz(a)<C && sz(b)<C) {
        if(sz(a)>=2) {
            int k=use_machine({a[0], in, a[1], in+1});
            if(k==0) a.pb(in), a.pb(in+1);
            else if(k==1) a.pb(in), b.pb(in+1);
            else if(k==2) b.pb(in), a.pb(in+1);
            else b.pb(in), b.pb(in+1);
            in+=2;
        }
        else {
            int k=use_machine({b[0], in, b[1], in+1});
            if(k==0) b.pb(in), b.pb(in+1);
            else if(k==1) b.pb(in), a.pb(in+1);
            else if(k==2) a.pb(in), b.pb(in+1);
            else a.pb(in), a.pb(in+1);
            in+=2;
        }
    }

    int ans=sz(a);
    if(sz(a)>=sz(b)) {
        vi tmp;
        FOR(i, 0, sz(a)) {
            tmp.pb(a[i]);
            if(in<n) tmp.pb(in++);
        }
        int k=use_machine(tmp);
        ans+=sz(a)-k/2-k&1;
    }
    else {
        vi tmp;
        FOR(i, 0, sz(b)) {
            tmp.pb(b[i]);
            if(in<n) tmp.pb(in++);
        }
        int k=use_machine(tmp);
        ans+=k/2+k&1;
    }

    return ans;
}
/*
3
0 1 0

10
0 1 1 0 0 0 1 1 1 1
*/

Compilation message (stderr)

mushrooms.cpp: In function 'int count_mushrooms(int)':
mushrooms.cpp:51:23: warning: suggest parentheses around '-' in operand of '&' [-Wparentheses]
   51 |         ans+=sz(a)-k/2-k&1;
      |                       ^
mushrooms.cpp:60:17: warning: suggest parentheses around '+' in operand of '&' [-Wparentheses]
   60 |         ans+=k/2+k&1;
      |              ~~~^~

• Subtask 1: 0 / 100