Submission #474231

#	Time	Username	Problem	Language	Result	Execution time	Memory
474231		MB2	Cave (IOI13_cave)	C++14	100 / 100	371 ms	540 KiB

cave

#include "cave.h"

#include <bits/stdc++.h>
using namespace std;
int c[5009], id[5009], t[5009];
void change(int l, int r) 
{
    for(int i=l; i<=r; i++) 
	{
        if(t[i]==0) 
		{
            c[i]^=1;
        }
    }
}
void exploreCave(int N) 
{
    for(int i=0; i<N; i++) 
	{
        int l=0, r=N-1, K;
        int f=tryCombination(c)==i;
        while(r-l>=0)
		{
            int mid=(l + r)>>1;
            change(l, mid);
            if ((tryCombination(c)==i)==f) 
			{
                change(l, mid);
                l=mid+1;
            } else 
			{
                change(l, mid);
                r=mid-1;
				K=mid;
            }
        }
        t[K]=1;
        id[K]=i;
        c[K]=f;
    }
    answer(c, id);
}

Compilation message (stderr)

cave.cpp: In function 'void exploreCave(int)':
cave.cpp:39:13: warning: 'K' may be used uninitialized in this function [-Wmaybe-uninitialized]
   39 |         c[K]=f;
      |         ~~~~^~

• Subtask 1: 12 / 12
• Subtask 2: 13 / 13
• Subtask 3: 21 / 21
• Subtask 4: 30 / 30
• Subtask 5: 24 / 24