80分求调

#include<bits/stdc++.h>
using namespace std;
int main() {
	int n, t = 0, a = 0, f = 0, fans = 0, zans = 0;
	cin >> n;
	for (int i = 1; i <= n; i++) {
		//TODO
		cin >> a;
		if (f == 0 || a == t + 1) {
			//TODO
			fans++;
			if (fans > zans) {
				//TODO
				zans = fans;
			}
			t = a;
			f = 1;
		} else {
			//TODO
			fans = 0;
			f = 0;
		}
	}
	cout << zans + 1;
	return 0;
}