14_Largest_3-Same-Digit_Number_in_String.cpp

// 2264. Largest 3-Same-Digit Number in String

// 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 num with length 3.
// 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 num or 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 <= 1000
// num only consists of digits.

class Solution
{
public:
    string largestGoodInteger(string num)
    {
        vector<string> p = {"999", "888", "777", "666", "555", "444", "333", "222", "111", "000"};
        for (int i = 0; i < p.size(); i++)
        {
            if (num.find(p[i]) != string::npos)
            {
                return p[i];
            }
        }
        return "";
    }
};