You are given a string number representing a positive integer and a character digit.
Return the resulting string after removing exactly one occurrence of digit from number such that the value of the resulting string in decimal form is maximized. The test cases are generated such that digit occurs at least once in number.
Example 1:
Input: number = "123", digit = "3" Output: "12" Explanation: There is only one '3' in "123". After removing '3', the result is "12".
Example 2:
Input: number = "1231", digit = "1" Output: "231" Explanation: We can remove the first '1' to get "231" or remove the second '1' to get "123". Since 231 > 123, we return "231".
Example 3:
Input: number = "551", digit = "5" Output: "51" Explanation: We can remove either the first or second '5' from "551". Both result in the string "51".
Constraints:
2 <= number.length <= 100number consists of digits from '1' to '9'.digit is a digit from '1' to '9'.digit occurs at least once in number.public class Solution {
public boolean canChange(String start, String target) {
int startLength = start.length();
// Pointers for start string and target string
int startIndex = 0, targetIndex = 0;
while (startIndex < startLength || targetIndex < startLength) {
// Skip underscores in start
while (
startIndex < startLength && start.charAt(startIndex) == '_'
) {
startIndex++;
}
// Skip underscores in target
while (
targetIndex < startLength && target.charAt(targetIndex) == '_'
) {
targetIndex++;
}
// If one string is exhausted, both should be exhausted
if (startIndex == startLength || targetIndex == startLength) {
return startIndex == startLength && targetIndex == startLength;
}
// Check if the pieces match and follow movement rules
if (
start.charAt(startIndex) != target.charAt(targetIndex) ||
(start.charAt(startIndex) == 'L' && startIndex < targetIndex) ||
(start.charAt(startIndex) == 'R' && startIndex > targetIndex)
) return false;
startIndex++;
targetIndex++;
}
// If all conditions are satisfied, return true
return true;
}
}class Solution {
public String removeDigit(String number, char digit) {
char[] cs = number.toCharArray();
for (int i = 0; i < cs.length - 1; i++) {
if (cs[i] == digit && digit < cs[i + 1])
return String.valueOf(number.substring(0, i) + number.substring(i + 1));
}
int li = number.lastIndexOf(digit);
return String.valueOf(number.substring(0, li) + number.substring(li + 1));
}
}