大话数据结构—串（九）

1.朴素的模式匹配算法

public class StringPatternMatch {

    public static void main(String[] args) {
        String src = "abcdef";
        String sub = "de";
        System.out.println(match(src,sub));
    }

    public static int match(String src, String sub) {
        int i = 0, j = 0;
        int index = -1;
        while (i < src.length() && j < sub.length()) {
            if (src.charAt(i) == sub.charAt(j)) {
                i++;
                j++;
            } else {
                i = i - j + 1;
                j = 0;
            }
        }
        if (j == sub.length()) {
            index = i - j;
        }
        return index;
    }

}