LeetCode-in-Java
2264. Largest 3-Same-Digit Number in String
Easy
You are given a string num representing a large integer. An integer is good if it meets the following conditions:
- It is a substring of
numwith length3. - It consists of only one unique digit.
Return the maximum good integer as a string or an empty string "" if no such integer exists.
Note:
- A substring is a contiguous sequence of characters within a string.
- There may be leading zeroes in
numor a good integer.
Example 1:
Input: num = “6777133339”
Output: “777”
Explanation: There are two distinct good integers: “777” and “333”.
“777” is the largest, so we return “777”.
Example 2:
Input: num = “2300019”
Output: “000”
Explanation: “000” is the only good integer.
Example 3:
Input: num = “42352338”
Output: “”
Explanation: No substring of length 3 consists of only one unique digit. Therefore, there are no good integers.
Constraints:
3 <= num.length <= 1000numonly consists of digits.
Solution
public class Solution {
public String largestGoodInteger(String num) {
String maxi = "000";
int c = 0;
for (int i = 0; i < num.length() - 2; i++) {
String s = num.substring(i, i + 3);
if (s.charAt(0) == s.charAt(1) && s.charAt(1) == s.charAt(2)) {
if (s.compareTo(maxi) >= 0) {
maxi = s;
}
++c;
}
}
if (c == 0) {
return "";
}
return maxi;
}
}