Lituo's daily question: The second largest number in a string [Thinking Simulation Water Question]

Give you a mixed string  s , please return  s the  second largest  number, if there is no second largest number, please return  -1 .

Mixed strings  consist of lowercase English letters and numbers.

Example 1:

Input: s = "dfa12321afd"
 Output: 2
 Explanation: The numbers appearing in s include [1, 2, 3]. The second largest number is 2 .

Example 2:

Input: s = "abc1111"
 Output: -1
 Explanation: The numbers appearing in s only contain [1]. There is no second largest number.

hint:

• 1 <= s.length <= 500
• s Contains only lowercase English letters and/or numbers.

Analysis: The given string is a mixture, define two variables, fMax is the maximum value, sMax represents the second maximum value, we traverse it once, and need to judge that the corresponding character c is between '0' and '9' Between if(c>='0'&&c<='9'), if the condition is met, then we are judging whether it is greater than fMax, if((c-'0')>fMax), if the condition is met, first fMax = sMax, smax = c-'0',

If the condition is not met: judge whether c-'0' satisfies the (c-'0')<fMax&&(c-'0')>sMax condition, if so, assign it to the second largest value sMax = c-'0 ' ; Finally, we can return sMax

AC code:

class Solution {
    public int secondHighest(String s) {
        int fMax = -1 ;
        int sMax = -1 ; 
        for(int i=0 ;i<s.length();i++){
            char c = s.charAt(i);
            if(c>='0'&&c<='9'){
                if((c-'0')>fMax){
                    sMax = fMax ; 
                    fMax = c-'0';

                }else  {
                    if((c-'0')<fMax&&(c-'0')>sMax){
                        sMax = c-'0' ; 
                    }
                }
            }
        }

        return sMax ; 
    }
}