牛客题目：找出给定字符串中大写字符(即‘A‘

牛客题目：找出给定字符串中大写字符(即‘A‘

疑问：假设极限情况下输入的字符串足够长一次读取一行会导致OOM，这题目要怎么处理？

牛客题目：找出给定字符串中大写字符(即'A'-'Z')的个数。

牛客链接：=37&&tqId=21307&rp=1&ru=/ta/huawei&qru=/ta/huawei/question-ranking

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;/*** 找出给定字符串中大写字符(即'A'-'Z')的个数。* */
public class HJ84 {public static void main(String[] args) throws IOException {List<Character> target = new ArrayList<>(26);for (char i='A'; i<='Z'; ++i) {target.add(i);}BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));String line = null;while((line&#adLine())!=null) {int count = 0;for (int i = 0; i < line.length(); i++) {if (ains(line.charAt(i))) {count++;}}System.out.println(count);}}
}

用lamba表达式改进下

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.IntStream;/*** 找出给定字符串中大写字符(即'A'-'Z')的个数。* */
public class HJ84 {public static void main(String[] args) throws IOException {List<Integer> target = new ArrayList<>(26);IntStream.rangeClosed('A', 'Z').forEach(ch->target.add(ch));BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));String line = null;while((line&#adLine())!=null) {long count = line.chars().filter(target::contains).count();System.out.println(count);}}
}