代码见下，思路应该没问题 勿喷！！！

#include <bits/stdc++.h>
using namespace std;
int a, b;

int main() {
	/*
	-------------
	学习新知逝
	-------------
	_Anonymous./
	-------------
	争做新氢年
	-------------
	*/
	cin >> a >> b;
	if (a < 0 && b < 0) {
		cout << abs(min(a, b));
		return 0;
	}
	if (a == 0 && b == 0) {
		cout << 0;
		return 0;
	}
	if (a > 0 && b > 0) {
		cout << max(a, b);
		return 0;
	}
	if (a == 0 && b != 0) {
		cout << abs(b);
		return 0;
	}
	if (b == 0 && a != 0) {
		cout << abs(a);
		return 0;
	}
	cout << max(a, b) + max(a, b) + abs(min(a, b));
	return 0;
}