Submission #2072172

---

Source Code Expand

#include <cstdio>
#include <cassert>
#include <algorithm>
using namespace std;
int N, L, p[200009], a, b; long long s[200009];
int main() {
	scanf("%d %d", &N, &L);
	for(int i = 0; i < N; i++) {
		scanf("%d %d %d", &p[i], &a, &b);
		s[i + 1] = s[i] + a - b;
	}
	p[N] = p[0] + L;
	for(int i = N + 1; i <= 2 * N; i++) p[i] = p[i - N] + L, s[i] = s[i - N];
	long long l = -1LL << 40, r = 1LL << 40;
	while(r - l > 1) {
		long long m = (l + r) >> 1;
		int cnt = 0;
		for(int i = 1; i <= N; i++) {
			if(s[i] < m) cnt += p[i] - p[i - 1];
		}
		if(2 * cnt < L) l = m;
		else r = m;
	}
	int pos = -1;
	for(int i = 0; i < N; i++) {
		if(s[i] == l) pos = i;
	}
	assert(pos != -1);
	long long ret = 0;
	for(int i = pos; i < N + pos; i++) {
		if(s[i] == s[i + 1]) continue;
		if(s[i] < s[i + 1]) {
			if(s[i] <= l && l <= s[i + 1]) {
				ret += max(l - s[i], 0LL) * p[i];
				ret -= max(s[i + 1] - l, 0LL) * p[i];
			}
			else {
				ret += (s[i + 1] - s[i]) * p[i] * (s[i] > l ? -1 : 1);
			}
		}
		else {
			if(s[i + 1] <= l && l <= s[i]) {
				ret += max(s[i] - l, 0LL) * p[i];
				ret -= max(l - s[i + 1], 0LL) * p[i];
			}
			else {
				ret += (s[i] - s[i + 1]) * p[i] * (s[i] > l ? 1 : -1);
			}
		}
	}
	printf("%lld\n", ret);
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:7:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d", &N, &L);
                        ^
./Main.cpp:9:35: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d %d", &p[i], &a, &b);
                                   ^

Judge Result