leetcode392 判断字符串 s 是否为 t 的子序列

女爷i 2024-03-27 11:34 78阅读 0赞

> [牛客华为机试题库【题号 HJ开头】（重点看）][HJ]  
> [牛客在线编程算法篇【题号NC开头】][NC]  
> [剑指offer【题号 JZ开头】][offer_ JZ]  
> [力扣][Link 1]

### 1）[原题链接][Link 2] ###

### 2）已有题解 ###

### 3）代码 ###

package string;
    
    import java.io.BufferedReader;
    import java.io.IOException;
    import java.io.InputStreamReader;
    
    import static java.lang.System.in;
    
    /**
     * leetcode392 判断字符串 s 是否为 t 的子序列
     * abc
     * ahbgdc
     * <p>
     * axc
     * ahbgdc
     */
    public class Leetcode392IsSubSequence {
        
        public static void main(String[] args) throws IOException {
        
            // 收集数据源
            BufferedReader bf = new BufferedReader(new InputStreamReader(in));
            String s = bf.readLine();
            String t = bf.readLine();
            bf.close();
    
            boolean res = isSubsequence(s, t);
    
            // 输出结果
            System.out.println(res);
        }
    
        private static boolean isSubsequence2(String s, String t) {
        
            if (s.length() == 0) {
        
                return true;
            }
            if (t.length() == 0) {
        
                return false;
            }
    
            // 快慢指针
            int slow = 0;
            for (int fast = 0; fast < t.length(); fast++) {
        
                if (s.charAt(slow) == t.charAt(fast)) {
        
                    slow++; // 相等的话指向慢指针的下个位置
                    if (slow >= s.length()) {
        
                        return true;
                    }
                }
            }
    
            return false;
        }
    
        /**
         * 判断字符串 s 是否为 t 的子序列
         */
        private static boolean isSubsequence(String s, String t) {
        
            if (s.length() == 0) {
        
                return true;
            }
            if (t.length() == 0) {
        
                return false;
            }
    
            char[] son = s.toCharArray();
            char[] mother = t.toCharArray();
    
            int index = 0;
            for (int i = 0; i < mother.length; i++) {
        
                if (mother[i] == son[index]) {
        
                    if (index >= son.length - 1) {
         // 最后一个字符是相等的
                        return true;
                    }
                    index++; // 当前字符处理完指针挪到下个位置，为后续做准备
                }
            }
    
            return false;
        }
    
        /**
         * 过于讨巧了
         */
        public boolean isSubsequence1(String s, String t) {
        
            int n = s.length();
            int m = t.length();
            int i = 0;
            int j = 0;
            while (i < n && j < m) {
        
                if (s.charAt(i) == t.charAt(j)) {
        
                    i++;
                }
                j++;
            }
            return i == n;
        }
    }

[HJ]: https://www.nowcoder.com/exam/oj/ta?tpId=37
[NC]: https://www.nowcoder.com/exam/oj
[offer_ JZ]: https://www.nowcoder.com/exam/oj/ta?page=1&tpId=13&type=13
[Link 1]: https://leetcode.cn/problemset/all/
[Link 2]: https://leetcode.cn/problems/is-subsequence/