Submission #562493

#	Time	Username	Problem	Language	Result	Execution time	Memory
562493		Iwanttobreakfree	Finding Routers (IOI20_routers)	C++17	98.76 / 100	2 ms	636 KiB

routers

#include "routers.h"
#include <vector>
using namespace std;
vector<int> guarda(100001,-1);
vector<int> find_routers(int lon, int n, int q) {
    vector<int> ans(n);
    vector<int> maxinum(n,1);
    vector<int> mininum(n,lon);
    ans[0]=guarda[0]=0;
    int l=0,r;
    for(int i=1;i<n;i++){
    l=maxinum[i-1];
    r=mininum[i];
    int sol;
    while(l<=r){
    	int mid=(l+r)/2,cerc;
    	if(guarda[mid]==-1)guarda[mid]=use_detector(mid);
    	cerc=guarda[mid];
    	if(cerc<i){
    		l=mid+1;
    		sol=mid;
		}
		else r=mid-1;
		if(maxinum[cerc]<mid)maxinum[cerc]=mid;
		if(mininum[cerc]>mid)mininum[cerc]=mid;
	}
	ans[i]=2*sol-ans[i-1];
	}
	return ans;
}

Compilation message (stderr)

routers.cpp: In function 'std::vector<int> find_routers(int, int, int)':
routers.cpp:27:10: warning: 'sol' may be used uninitialized in this function [-Wmaybe-uninitialized]
   27 |  ans[i]=2*sol-ans[i-1];
      |         ~^~~~

• Subtask 1: 16 / 16
• Subtask 2: 21 / 21
• Subtask 3: 23 / 23
• Subtask 4: 38.7584 / 40