Submission #88868

#	Time	Username	Problem	Language	Result	Execution time	Memory
88868		123456	Triumphal arch (POI13_luk)	C++14	100 / 100	1586 ms	25404 KiB

luk

#include <bits/stdc++.h>

using namespace std;

int n;
vector < int > G[300020];
int answer[300020];

void go(int v, int p, int x){
  int tot = 0;
  for(int i = 0; i < G[v].size(); ++ i){
    if(G[v][i] == p)
      continue;
    go(G[v][i], v, x);
    tot += answer[G[v][i]] + 1;
  }
  answer[v] = max(0, tot - x);
}

int main(){
  scanf("%d", &n);
  for(int i = 1; i < n; ++ i){
    int x, y;
    scanf("%d %d", &x, &y);
    G[x].push_back(y);
    G[y].push_back(x);
  }
  int l = 0;
  int r = n;
  while(l < r){
    int mid = (l + r) / 2;
    go(1, 0, mid);
    if(answer[1])
      l = mid + 1;
    else
      r = mid;
  }
  printf("%d", l);
}

Compilation message (stderr)

luk.cpp: In function 'void go(int, int, int)':
luk.cpp:11:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i = 0; i < G[v].size(); ++ i){
                  ~~^~~~~~~~~~~~~
luk.cpp: In function 'int main()':
luk.cpp:21:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &n);
   ~~~~~^~~~~~~~~~
luk.cpp:24:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d", &x, &y);
     ~~~~~^~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10