Submission #200035

#	Time	Username	Problem	Language	Result	Execution time	Memory
200035		wilwxk	Lightning Rod (NOI18_lightningrod)	C++14	66 / 100	2017 ms	164624 KiB

Main

#include <bits/stdc++.h>
using namespace std;

set<pair<int, int> > s;
int n;

int main() {
	scanf("%d", &n);
	for(int i = 1; i <= n; i++) {
		int a, b; scanf("%d %d", &a, &b);
		int x = a+b; int y = b-a;
		
		auto sit = s.lower_bound({x, y});
		if(sit != s.end() && sit->second >= y) continue;
		if(sit != s.end() && make_pair(x, y) > (*sit)) sit = prev(s.erase(sit));
		while(sit != s.begin() && prev(sit)->second <= y) sit = s.erase(prev(sit));
		s.insert({x, y});
	}

	printf("%d\n", int(s.size()));
}

Compilation message (stderr)

lightningrod.cpp: In function 'int main()':
lightningrod.cpp:8:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &n);
  ~~~~~^~~~~~~~~~
lightningrod.cpp:10:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   int a, b; scanf("%d %d", &a, &b);
             ~~~~~^~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 4
• Subtask 2: 7 / 7
• Subtask 3: 12 / 12
• Subtask 4: 21 / 21
• Subtask 5: 26 / 26
• Subtask 6: 0 / 10
• Subtask 7: 0 / 20