Submission #333139

#	Time	Username	Problem	Language	Result	Execution time	Memory
333139		qwe854896	Strange Device (APIO19_strange_device)	C++14	100 / 100	871 ms	83264 KiB

strange_device

#include<bits/stdc++.h>
#define endl '\n'
#define int long long
#define X first
#define Y second
using namespace std;

map <int, int> m;

signed main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);
	int n, A, B;
	cin >> n >> A >> B;
	int ans = 0, MOD = log10(A) - log10(__gcd(A, B+1)) + log10(B) > 18 ? (long long)(1e18+1) : A / __gcd(A, B+1) * B;
	while (n--) {
		int l, r;
		cin >> l >> r;
		int L = l % MOD, R = r % MOD;
		if (r - l >= MOD) ans = MOD;
		else if (L < R) m[L]++, m[R+1]--;
		else if (L > R) m[L]++, m[MOD]--, m[0]++, m[R+1]--;
		else if (l == r) m[L]++, m[L+1]--;
		else ans = MOD;
	}
	int sum = 0, f = 1, l;
	if (ans != MOD) {
		for (auto seg:m) {
			//cout << seg.X << ' ' << seg.Y << endl;
			sum += seg.Y;
			if (sum and f) l = seg.X, f = 0;
			else if (!sum) ans += seg.X - l, f = 1;
		}
	}
	cout << ans << endl;
	return 0;
}

Compilation message (stderr)

strange_device.cpp: In function 'int main()':
strange_device.cpp:33:32: warning: 'l' may be used uninitialized in this function [-Wmaybe-uninitialized]
   33 |    else if (!sum) ans += seg.X - l, f = 1;
      |                          ~~~~~~^~~

• Subtask 1: 10 / 10
• Subtask 2: 5 / 5
• Subtask 3: 5 / 5
• Subtask 4: 5 / 5
• Subtask 5: 5 / 5
• Subtask 6: 20 / 20
• Subtask 7: 20 / 20
• Subtask 8: 30 / 30