#!/usr/bin/python

def reverse(x):
    a = str(x)
    l = []
    sign = '';
    for c in a:
        if c == '-':
            sign = c
            continue
        l.append(c);

    l.reverse();

    while len(l) > 1:
        c = l.pop();
        if c != '0':
            l.append(c)
            break

    n = int(sign+''.join(l));

    if n < -2**31 or n > 2**31-1:
        return 0
    else:
        return n

if __name__ == '__main__':
    print reverse(123)
    print reverse(-123)
    print reverse(120)
    print reverse(1534236469)
			

#!/usr/bin/python

def reverse(x):
    sign = False
    if x < 0:
        sign = True

    re = 0
    x = abs(x)
    while x > 0:
        re = re*10 + x%10
        print re
        x = x/10

    if sign:
        re = 0 - re

    if re < -2**31 or re > 2**31-1:
        return 0
    else:
        return re

if __name__ == '__main__':
    print reverse(123)
    print reverse(-123)
    print reverse(120)
    print reverse(1534236469)
    print reverse(0)
			

#!/usr/bin/python

def reverse(x):
    if x == 0:
        return 0;

    sign = ''
    if x < 0:
        sign = '-'

    a = str(x)

    start = False
    l = []

    for i in xrange(len(a)-1, -1, -1):
        if not start and a[i] != '0':
            start = True
        if start and a[i] != '-':
            l.append(a[i]);

    n = int(sign+''.join(l));

    if n < -2**31 or n > 2**31-1:
        return 0
    else:
        return n

if __name__ == '__main__':
    print reverse(123)
    print reverse(-123)
    print reverse(120)
    print reverse(1534236469)
    print reverse(0)