KMP

Java代码

import java.io.*;

/**
 * @author jeffery.ma
 * @date 2022/10/24 13:56
 */

public class Main {

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
        int n = Integer.parseInt(br.readLine());
        String ps = ' ' + br.readLine();
        int m = Integer.parseInt(br.readLine());
        String ss = ' ' + br.readLine();
        int[] ne = new int[ps.length()];
        char[] p = ps.toCharArray();
        char[] s = ss.toCharArray();
        for (int i = 2, j = 0; i <= n; i ++) {
            while (j > 0 && p[i] != p[j + 1]) j = ne[j];
            if (p[i] == p[j + 1]) j ++;
            ne[i] = j;
        }

        for (int i = 1, j = 0; i <= m; i ++) {
            while (j > 0 && s[i] != p[j + 1]) j = ne[j];
            if (s[i] == p[j + 1]) j ++;
            if (j == n) {
                bw.write(i - n + " ");
                j = ne[j];
            }
        }
        bw.flush();
    }
}