算法--2023.1.27

1.力扣394--字符串解码

class Solution {
    public String res;
    public int i;
    public String decodeString(String s) {
        res = new String();
        int n = s.length();
        i = 0;
        for(;i<n;i++){
            int k = s.charAt(i) - '0';
            //System.out.println(k);
            if(k>=1&&k<=9){
                int num = k;
                i++;
                while(s.charAt(i)-'0'>=0&&s.charAt(i)-'0'<=9){
                    num = num*10+(s.charAt(i)-'0');
                    i++;
                }
                //System.out.println(num);
               res += dfs(s,num);
            }else{
                res += s.charAt(i);
            }
        }
        return res;
    }
    public String dfs(String s,int k){
        String temp = new String();
        i++;
        while(i<s.length()){
            int kk = s.charAt(i) - '0';
            //System.out.println(s.charAt(t));
            if(kk>=1&&kk<=9){
                int num = kk;
                i++;
                while(s.charAt(i)-'0'>=0&&s.charAt(i)-'0'<=9){
                    num = num*10+(s.charAt(i)-'0');
                    i++;
                }
                //System.out.println(num);
                temp += dfs(s,num);
            }else if(s.charAt(i) == ']'){
                String cur = new String();
                for(int p = 0;p<k;p++){
                    cur += temp;
                    //System.out.println(temp);
                }
                //System.out.println(k);
                return cur;
            }else{
                temp += s.charAt(i);
                //System.out.println(temp);
            }
            i++;
        }
        return temp;
    }
}