C - Busy Robot

模擬

nx : 當前傳送當前這次命令時機器人的位置

ed：當前正在執行的操作的結束時間

d：當前的方向

#include <iostream>
#include <cstring>
#include <algorithm>
#include <vector>
#include <cmath>

using namespace std;
typedef long long ll;
const int N = 1e5 + 10;
const ll INF = 1e18;
int n;
ll t[N], x[N];
int main()
{
	ios::sync_with_stdio(false), cin.tie(0), cout.tie(0);
	int T;
	cin >> T;
	while(T--)
	{
		cin >> n;
		for (int i = 1; i <= n; i++)
			cin >> t[i] >> x[i];
		t[n+1] = INF;
		ll nx = 0, ed = 0, d = 0;
		int cnt = 0;
		for (int i = 1; i <= n; i++)
		{
			nx += (min(t[i], ed) - t[i-1]) * d;
			if (t[i] >= ed)
			{
				ed = t[i] + abs(nx - x[i]);
				d = (x[i] >= nx ? 1 : -1);
				
			}
			int l = nx, r = nx + (min(t[i+1], ed) - t[i]) * d;
			if (l > r)
				swap(l, r);
			if (x[i] >= l && x[i] <= r)
				cnt++;
		}
		cout << cnt << endl;
	}
	return 0;
}