求解一个计算字符串中出现的数字之和问题

[兔兔土土]

[兔兔土土]

引用 2 楼 nayi_224 的回复：

		String str = "1a2a3";
		
		Pattern pattern = Pattern.compile("[0-9]+");
		Matcher matcher = pattern.matcher(str);
		
		int aa = 0;
		
		while(matcher.find()){
			aa += Integer.valueOf(matcher.group());
		}
		
		System.out.println(aa);

多谢老哥，不过正则最近还没学到，最近学的IO流 您的解答我得好好研究研究，哈哈哈

[游北亮]

正则是比较简单的作法，给你一个不用正则的：

int num = 0;
String lastNum = "";
String str = "1a2b3c44d";
for (int i = 0; i < str.length(); i++) {
    char ch = str.charAt(i);
    if (ch >= '0' && ch <= '9') {
        lastNum += ch;
        continue;
    }
    if (lastNum.length() > 0) {
        num += Integer.valueOf(lastNum);
        lastNum = "";
    }
}
if (lastNum.length() > 0)
    num += Integer.valueOf(lastNum);
System.out.println(num);

[兔兔土土]

这种如何得到里面的数字，有大神嘛

[兔兔土土]

引用 4 楼 水边2 的回复：

正则是比较简单的作法，给你一个不用正则的：

int num = 0;
String lastNum = "";
String str = "1a2b3c44d";
for (int i = 0; i < str.length(); i++) {
    char ch = str.charAt(i);
    if (ch >= '0' && ch <= '9') {
        lastNum += ch;
        continue;
    }
    if (lastNum.length() > 0) {
        num += Integer.valueOf(lastNum);
        lastNum = "";
    }
}
if (lastNum.length() > 0)
    num += Integer.valueOf(lastNum);
System.out.println(num);

牛逼老哥，多谢了！

[nayi_224]

		String str = "1a2a3";
		
		Pattern pattern = Pattern.compile("[0-9]+");
		Matcher matcher = pattern.matcher(str);
		
		int aa = 0;
		
		while(matcher.find()){
			aa += Integer.valueOf(matcher.group());
		}
		
		System.out.println(aa);

[qq_40674493]

		String str = "6ab11c333def521gh9i5jk61nm3n2";
		StringBuffer buffer = new StringBuffer();
		int sum = 0;
		char c;
		for (int i = 0; i < str.length(); i++) {
			c = str.charAt(i);
			if (Character.isDigit(c)) {//使用Java类库的方法判断字符是否是数字
				buffer.append(c);
			} else if (buffer.length() > 0) {
				sum += Integer.parseInt(buffer.toString());
				buffer.delete(0, buffer.length());//清空缓存
			}
		}
		if (buffer.length() > 0) {
			sum += Integer.parseInt(buffer.toString());
		}
		System.out.println(sum);

[嗯嗯**]

class text {
	public static int count(String str) {
		char[] s = str.toCharArray();
		String number = "";
		int sum = 0;
		for(int i = 0; i < s.length; i++) {
			if(s[i] > 47 && s[i] < 58 ) {
				number =number + s[i];
				if(i != (s.length - 1)) {
					println(i);
					continue;
				}
			}
			if(number.length() > 0) {
				sum += Integer.valueOf(number);
				number="";
			}			
		}
		return sum;
	}
}

[qq_43252604]

转换成字符数组，遍历