Submission #119499

#	Time	Username	Problem	Language	Result	Execution time	Memory
119499		tmwilliamlin168	Printed Circuit Board (CEOI12_circuit)	C++14	0 / 100	41 ms	5880 KiB

circuit

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

#define ll long long

const int mxN=2e5;
int n, l, r;
ll x[mxN+1], y[mxN+1];
vector<int> v, s;

ll cp(int a, int b, int c) {
	return (y[c]-y[a])*(x[b]-x[a])-(y[b]-y[a])*(x[c]-x[a]);
}

int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	
	cin >> n;
	while(n<3);
	for(int i=0; i<n; ++i) {
		cin >> x[i] >> y[i];
		if(!i||cp(n, l, i)>0||!cp(n, l, i)&&x[i]<x[l])
			l=i;
		if(!i||cp(n, r, i)<0||!cp(n, r, i)&&x[i]<x[r])
			r=i;
	}
	cout << s.size() << "\n";
	sort(s.begin(), s.end());
	for(int a : s)
		cout << a+1 << " ";
}

Compilation message (stderr)

circuit.cpp: In function 'int main()':
circuit.cpp:23:37: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   if(!i||cp(n, l, i)>0||!cp(n, l, i)&&x[i]<x[l])
                         ~~~~~~~~~~~~^~~~~~~~~~~
circuit.cpp:25:37: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   if(!i||cp(n, r, i)<0||!cp(n, r, i)&&x[i]<x[r])
                         ~~~~~~~~~~~~^~~~~~~~~~~

• Subtask 1: 0 / 100