Submission #629389

#	Time	Username	Problem	Language	Result	Execution time	Memory
629389		Stavab	Cave (IOI13_cave)	C++14	0 / 100	79 ms	460 KiB

cave

#include "cave.h"

void exploreCave(int n)
{
    int s[n], d[n];
    for(int i = 0; i < n; i++)
    {
        s[i] = 0;
        d[i] = -1;
    }
    
    int cur, prev, door;
    for(int i = 0; i < n; i++)
    {
        door = tryCombination(s);
        if(door > i || door == -1)
            prev = 1;
        else
            prev = 0;
        
        int low = 0, high = n;
        while(high - low > 1)
        {
            int middle = (low + high) / 2;
            
            for(int j = low; j <= middle; j++)
            {
                if(d[j] != -1) continue;
                
                if(s[j]) s[j] = 0;
                else s[j] = 1;
            }
            
            door = tryCombination(s);
            if(door > i || door == -1)
                cur = 1;
            else
                cur = 0;
                
            if(cur == prev)
                low = middle;
            else
                high = middle;
            prev = cur;
        }
        
        if(d[low] == -1)
        {
            if(s[low]) s[low] = 0;
            else s[low] = 1;
            
            door = tryCombination(s);
            if(door > i || door == -1)
                cur = 1;
            else
                cur = 0;
        }
        
        int ind;
        if(cur == prev)
        {
            d[high] = i;
            ind = high;
        }
        else
        {
            d[low] = i;
            ind = low;
        }
        
        door = tryCombination(s);
        if(door <= i)
        {
            if(s[ind]) s[ind] = 0;
            else s[ind] = 1;
        }
    }
    
    answer(s, d);
}

Compilation message (stderr)

cave.cpp: In function 'void exploreCave(int)':
cave.cpp:60:9: warning: 'cur' may be used uninitialized in this function [-Wmaybe-uninitialized]
   60 |         if(cur == prev)
      |         ^~

• Subtask 1: 0 / 12
• Subtask 2: 0 / 13
• Subtask 3: 0 / 21
• Subtask 4: 0 / 30
• Subtask 5: 0 / 24