Codeforces Round #171 (Div. 2) A. Point on Spiral（模拟）

Valera the horse lives on a plane. The Cartesian coordinate system is defined on this plane. Also an infinite spiral is painted on the plane. The spiral consists of segments: [(0, 0), (1, 0)], [(1, 0), (1, 1)], [(1, 1), ( - 1, 1)], [( - 1, 1), ( - 1, - 1)], [( - 1, - 1), (2, - 1)], [(2, - 1), (2, 2)] and so on. Thus, this infinite spiral passes through each integer point of the plane.

Valera the horse lives on the plane at coordinates (0, 0). He wants to walk along the spiral to point (x, y). Valera the horse has four legs, so he finds turning very difficult. Count how many times he will have to turn if he goes along a spiral from point (0, 0) to point (x, y).

Input

The first line contains two space-separated integers x and y (|x|, |y| ≤ 100).

Output

Print a single integer, showing how many times Valera has to turn.

Sample test(s)

Input

0 0

Output

Input

1 0

Output

Input

0 1

Output

Input

-1 -1

Output

这题做了好久……囧

AC Code:

 1 #include <iostream>
 2 #include <string>
 3 #include <set>
 4 #include <map>
 5 #include <vector>
 6 #include <stack>
 7 #include <queue>
 8 #include <cmath>
 9 #include <cstdio>
10 #include <cstring>
11 #include <algorithm>
12 using namespace std;
13 #define LL long long
14 #define cti const int
15 #define ctll const long long
16 #define dg(i) cout << "*" << i << endl;
17 
18 int main()
19 {
20     int x, y, ans;
21     while(scanf("%d %d", &x, &y) != EOF)
22     {
23         if(abs(x) > abs(y))
24         {
25             if(x == 1) ans = 0;
26             else if(x > 0) ans = (x - 1)* 4 + (x != 1 - y);
27             else ans = (-x - 1) * 4 + 3;
28         }
29         else
30         {
31             if(!y) ans = 0;
32             else if(y > 0) ans = (y - 1) * 4 + 2;
33             else ans = (-y - 1) * 4 + 4;
34             ans -= (x == y && x);
35         }
36         printf("%d\n", ans);
37     }
38     return 0;
39 }