Submission #402244

#	Time	Username	Problem	Language	Result	Execution time	Memory
402244		victoriad	Finding Routers (IOI20_routers)	C++14	100 / 100	3 ms	672 KiB

routers

#include "routers.h"
using namespace std;

std::vector<int> find_routers(int l, int n, int q) {
    std::vector<int> ans(n);
    vector<int>s(l+1,-1);
    ans[0]=0;
    s[0]=0;
    if(l%2==1)l--;
    for(int i=1;i<n;i++){
      int low=1,hi=l,r;
      while(low<=hi){
        int mid=(low+hi)/2;
        if(s[mid]==-1){
          s[mid]=use_detector(mid);
        }
        if(s[mid]>=i){
          hi=mid-1;
          r=mid;
        }
        else{
          low=mid +1;
        }
      }
      ans[i]=2*r-2-ans[i-1];
    }
	return ans;
}

Compilation message (stderr)

routers.cpp: In function 'std::vector<int> find_routers(int, int, int)':
routers.cpp:25:17: warning: 'r' may be used uninitialized in this function [-Wmaybe-uninitialized]
   25 |       ans[i]=2*r-2-ans[i-1];
      |              ~~~^~

• Subtask 1: 16 / 16
• Subtask 2: 21 / 21
• Subtask 3: 23 / 23
• Subtask 4: 40 / 40