华为2016校园招聘上机笔试题

1、匹配字符串后面跟数组取值，  例:object[1,2,3][0]； [0,1][2]；[123]

^\w*\[\s*(-?\d+\s*(,\s*-?\d+\s*)*)\](\[\s*(-?\d+\s*(,\s*-?\d+\s*)*)\s*\])*

Pattern pattern = Pattern.compile("^\\w*\\[\\s*(-?\\d+\\s*(,\\s*-?\\d+\\s*)*)\\](\\[\\s*(-?\\d+\\s*(,\\s*-?\\d+\\s*)*)\\s*\\])*");
       String[] strArr = {"object[1,2,3][0]", "[0,1][2]", "obj[10]", "[1]"};
       for (String str : strArr) {
           System.out.println(pattern.matcher(str).matches());
}

2、截取中括号里面的值

\[(.*?)\]

String[] strArr = {"object[1,2,3][0]", "[0,1][2]", "obj[10]", "[1]"};
        Pattern pattern = Pattern.compile("\\[(.*?)\\]");
        for (String strKey : strArr) {
            Matcher matcher = pattern.matcher(strKey);
            while (matcher.find()) {
//          System.out.println(matcher.group(0)); // 输出整个匹配的括号内内容
                System.out.println(matcher.group(1)); // 输出括号内的具体值
            }
            System.out.println("----------------------------");
        }

3、判断逗号分隔的数字是否全部为正整数

^\s*(\d+\s*,\s*)*\d*\s*$

        String[] strArr = {"1,2,3", "0", "8,a,1", "-1,99", "1,2.3","aa"};
        Pattern pattern = Pattern.compile("^\\s*(\\d+\\s*,\\s*)*\\d*\\s*$");
        for (String strKey : strArr) {
            Matcher matcher = pattern.matcher(strKey);
            System.out.println(matcher.matches());
        }