Submission #2113403

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Source Code Expand

#include <bits/stdc++.h>
#include <climits>
#define rep(i, begin, end) for (__typeof(end) i = (begin) - ((begin) > (end)); i != (end) - ((begin) > (end)); i += 1 - 2 * ((begin) > (end)))
#define srep(i, begin, end) for (__typeof(end) i = begin; i != end; i++)
#define si(x) int x = scanInt();
#define sll(x) LL x = scanLong();
#define sci(x) int x; scanf("%d", &x);
#define scll(x) LL x; scanf("%lld", &x);
#define pi(x) printf("%d ", x)
#define pll(x) printf("%lld ", x)
#define ps(x) printf("%s", x)
#define nl printf("\n")
#define clr(a) memset(a, 0, sizeof(a))
#define PB push_back
#define MP make_pair
using namespace std;
typedef unsigned int UI; // 32 bit integer
typedef long int LI; // 32 bit integer
typedef unsigned long int ULI; // 32 bit unsigned integer
typedef long long int LL; // 64 bit integer
typedef unsigned long long int  ULL; // 64 bit unsigned integer
typedef long double LD;
typedef vector<int> VI;
typedef vector<LL> VLL;
typedef pair<int, int> PII;
typedef pair<LL, LL> PLL;
LL mod = 1e9+7;

/* Fast I/O */
inline int scanInt() {
	int n = 0;
	char ch = getchar();
	int sign = 1;
	while(ch < '0' || ch > '9') {
		if(ch == '-')	sign = -1;
		ch = getchar();
	}
	while(ch >= '0' && ch <= '9') {
		n = (n<<1)+(n<<3)+(int)(ch-'0');
		ch = getchar();
	}
	return n*sign;
}

inline LL scanLong() {
	LL n = 0;
	char ch = getchar();
	LL sign = 1;
	while(ch < '0' || ch > '9') {
		if(ch == '-')	sign = -1;
		ch = getchar();
	}
	while(ch >= '0' && ch <= '9') {
		n = (n<<1)+(n<<3)+(LL)(ch-'0');
		ch = getchar();
	}
	return n*sign;
}

struct Point {
	LL xs, ys, xe, ye;
	Point(LL _xs, LL _ys, LL _xe, LL _ye) {
		if(_xs < _xe) {
			xs = _xs;
			ys = _ys;
			xe = _xe;
			ye = _ye;
		}
		else {
			xs = _xe;
			ys = _ye;
			xe = _xs;
			ye = _ys;
		}
	}
};

bool intersect(Point fi, Point sec) {
	LL a = (sec.ye - sec.ys);
	LL b = (sec.xs - sec.xe);
	LL c = sec.ys * (sec.xe - sec.xs) - sec.xs * (sec.ye - sec.ys);
	LL st = a * fi.xs + b * fi.ys + c;
	LL en = a * fi.xe + b * fi.ye + c;
	return (st * en <= 0);
}

int main() {
#ifndef ONLINE_JUDGE
	freopen("inp.txt", "r", stdin);
#endif
	sll(Y); sll(X); sll(n);
	vector<Point> ps;
	rep(i, 0, n) {
		sll(xs); sll(ys); sll(xe); sll(ye);
		if(((xs == 0 || xs == X) || (ys == 0 || ys == Y)) && ((xe == 0 || xe == X) || (ye == 0 || ye == Y)))
			ps.push_back(Point(xs, ys, xe, ye));
	}
	rep(i, 0, ps.size()) {
		rep(j, i+1, ps.size()) {
			if(intersect(ps[i], ps[j])) {
				puts("NO");
				return 0;
			}
		}
	}
	puts("YES");
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:89:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result]
  freopen("inp.txt", "r", stdin);
                                ^

Judge Result