Description
Given an integer, write an algorithm to convert it to hexadecimal. For negative integer, two’s complement method is used.
Note:
- All letters in hexadecimal (
a-f) must be in lowercase. - The hexadecimal string must not contain extra leading
0s. If the number is zero, it is represented by a single zero character'0'; otherwise, the first character in the hexadecimal string will not be the zero character. - The given number is guaranteed to fit within the range of a 32-bit signed integer.
- You must not use any method provided by the library which converts/formats the number to hex directly.
Example 1:
Input:
26
Output:
"1a"
Example 2:
Input:
-1
Output:
"ffffffff"
Solution
注意三目运算符别写错了。
class Solution {
public String toHex(int num) {
if (num == 0) {
return "0";
}
StringBuilder sb = new StringBuilder();
while (num != 0) {
int x = num & 0xf;
sb.insert(0, x < 10 ? x + "" : (char) ('a' + x - 10));
num >>>= 4;
}
return sb.toString();
}
}
