x = int(input())
y = 0
if x > 0:
    y = x + 1
elif x == 0:
    y = 0
elif x < 0:
    y = x - 1
print(y)
/**************************************************************
	Problem: 1038
	User: lzk
	Language: Python
	Result: Accepted
	Time:81 ms
	Memory:34244 kb
****************************************************************/