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7. Reverse Integer
Medium
Given a signed 32-bit integer x, return x with its digits reversed. If reversing x causes the value to go outside the signed 32-bit integer range [-231, 231 - 1], then return 0.
Assume the environment does not allow you to store 64-bit integers (signed or unsigned).
Example 1:
Input: x = 123
Output: 321
Example 2:
Input: x = -123
Output: -321
Example 3:
Input: x = 120
Output: 21
Example 4:
Input: x = 0
Output: 0
Constraints:
-231 <= x <= 231 - 1
Solution
# @param {Integer} x
# @return {Integer}
def reverse(x)
new_a = x.to_s.reverse.to_i
if x >= 0
new_a < (2 ** 31 - 1) ? new_a : 0
else
-new_a > (-2) ** 31 ? -new_a : 0
end
end