代码随想录训练营第八天

最新推荐文章于 2025-12-04 23:36:16 发布

原创最新推荐文章于 2025-12-04 23:36:16 发布 · 83 阅读

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#leetcode #数据结构

344

class Solution {
    public void reverseString(char[] s) {
        int l = 0;
        int r = s.length -1;
        while(l<r){
            char temp = s[l];
            s[l] = s[r];
            s[r] = temp;
            l++;
            r--;
        }
    }
}

541

class Solution {
    public String reverseStr(String s, int k) {
        char[] ch = s.toCharArray();
        for(int i = 0; i < ch.length ;i += 2 *k){
            int start = i;
            int end = Math.min(ch.length -1 ,start + k -1);
            while(start < end){
                char temp =ch[start];
                ch[start] = ch[end];
                ch[end] = temp;
                start++;
                end--;

            }
        }
        return new String(ch);
    }
}

剑指Offer 05

class Solution {
    public String replaceSpace(String s) {
        if(s ==null || s.length() == 0){
            return s;
        }
        StringBuilder str = new StringBuilder();
        for(int i =0; i <s.length();i++){
            if(s.charAt(i) == ' '){
                str.append("  ");
            }
        }
        if(str.length() == 0)
            return s;
        int left = s.length() - 1;
        s += str.toString();
        int right = s.length()-1;
        char[] chars = s.toCharArray();
        while(left>=0){
            if(chars[left] == ' '){
             chars[right--] = '0';
             chars[right--] = '2';
             chars[right] = '%';
            }else{
                  chars[right] = chars[left];
                 }
          left--;
            right--;
        }
    return new String(chars);
    }
}