java 代码

import java.io.*;
import java.lang.Integer;

class Main{
    static void next(int[] next, String s){//构造next前后缀数组
        int len = s.length();
        int i = 0, j = -1;
        next[0] = -1;
        while(i < len){
            if(j == -1 || s.charAt(i) == s.charAt(j)){
                i++;
                j++;
                next[i] = j;
            }else{
                j = next[j];
            }
        }
    }
    public static void main(String[] args)throws Exception{
        BufferedReader buf = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter buw = new BufferedWriter(new OutputStreamWriter(System.out));
        int n = Integer.valueOf(buf.readLine());
        String s = buf.readLine();
        int m = Integer.valueOf(buf.readLine());
        String p = buf.readLine();
        int[] next = new int[n + 10];//其实加1就可以了，因为kmp求next数组需要用到length+1位
        next(next, s);
        int i = 0, j = 0;
        while(i < m && j < n){
            if(j == -1 || p.charAt(i) == s.charAt(j)){//j == -1的目的是如果整个串都不匹配只能让i,j向后移动一位,重新开始匹配
                i++;
                j++;
            }else{
                j = next[j];
            }
            if(j == n){
                buw.write(i - j + " ");
                System.out.print(j);
                j = next[j];//匹配完成，j返回上一步
            }
        }
        buw.flush();
        buf.close();
        buw.close();
    }
}