Submission #373836

#	Time	Username	Problem	Language	Result	Execution time	Memory
373836		guka415	Lightning Rod (NOI18_lightningrod)	C++14	66 / 100	2093 ms	141740 KiB

Main

#define _CRT_SECURE_NO_WARNINGS

#include <iostream>
#include <algorithm>

using namespace std;
typedef pair<int, int> pii;

const int sz = 1e7 + 5;
int n;
int p[sz][2];
int mxx[sz], mny[sz];

int main() {
	int xp, yp, ret = 0, mx = -2e9;
	scanf("%d", &n);
	for (int i = 0; i < n; i++) {
		scanf("%d %d", &xp, &yp);
		p[i][0] = xp + yp;
		p[i][1] = xp - yp;
	}
	mxx[0] = p[0][0];
	for (int i = 1; i < n; i++)
		mxx[i] = (mxx[i - 1] < p[i][0] ? p[i][0] : mxx[i - 1]);
	mny[n - 1] = p[n - 1][1];
	for (int i = n - 2; i >= 0; i--)
		mny[i] = (mny[i + 1] > p[i][1] ? p[i][1] : mny[i + 1]);
	for (int i = 0; i < n; i++) {
		bool yes = 1;
		if (i && mxx[i - 1] >= p[i][0])
			yes = 0;
		if (i != n - 1 && mny[i + 1] <= p[i][1])
			yes = 0;
		ret += yes;
	}
	printf("%d", ret);
	return 0;
}

Compilation message (stderr)

lightningrod.cpp: In function 'int main()':
lightningrod.cpp:15:23: warning: unused variable 'mx' [-Wunused-variable]
   15 |  int xp, yp, ret = 0, mx = -2e9;
      |                       ^~
lightningrod.cpp:16:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   16 |  scanf("%d", &n);
      |  ~~~~~^~~~~~~~~~
lightningrod.cpp:18:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   18 |   scanf("%d %d", &xp, &yp);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~

• 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