[Java]化学反応式201912-3

import java.io.*; 
import java.util.Map;
import java.util.HashMap;
import java.util.StringTokenizer; 

public class Main 
{
    
     
	private static Map<String, Integer> handle(String expr) {
    
    
		// 系数
		Map<String, Integer> map = new HashMap<>();
		if (expr.equals("")) return map;
		int Coef = 0, i = 0;
		while (Character.isDigit(expr.charAt(i))) {
    
    
			Coef = Coef * 10 + expr.charAt(i) - '0';
			i++;
		}
		if (Coef == 0) Coef = 1;

		StringBuilder element = new StringBuilder();
		while (i < expr.length()) {
    
    
			// 元素后面的系数
			int coef = 0;
			char c = expr.charAt(i++);
			// i 为左括号
			if (c == '(') {
    
    
				int start = i;
				int parentheses = 1;
				while (i < expr.length() && parentheses != 0) {
    
    
					c = expr.charAt(i++);
					if (c == '(') {
    
    
						parentheses++;
					}
					if (c == ')') {
    
    
						parentheses--;
					}
				}
				int end = i - 1;
				// c 可能为系数ceof
				Map<String, Integer> subMap = handle(expr.substring(start, end));
				if (i < expr.length()) {
    
    
					c = expr.charAt(i++);
					while (Character.isDigit(c)) {
    
    
						coef = coef * 10 + c - '0';
						if (i < expr.length()) c = expr.charAt(i++);
						else break;
					}
					if (c >= 'A' && c <= 'Z' || c == '(') {
    
    
						i--;
					}
				}
				for (String key : subMap.keySet()) {
    
    
					map.put(key, map.getOrDefault(key, 0) + subMap.get(key) * Coef * (coef == 0 ? 1 : coef));
				}
			}
			// c 为大写字母
			else {
    
    
				element.append(c);
				if (i < expr.length()) {
    
    
					c = expr.charAt(i++);
					if (c >= 'a' && c <= 'z') {
    
    
						element.append(c);
						if (i < expr.length()) c = expr.charAt(i++);
					}
					// 计算元素后面的系数
					while (Character.isDigit(c)) {
    
    
						coef = coef * 10 + c - '0';
						if (i < expr.length()) c = expr.charAt(i++);
						else break;
					}
					if (c >= 'A' && c <= 'Z' || c == '(') {
    
    
						i--;
					}
				}
				map.put(element.toString(), map.getOrDefault(element.toString(), 0) + Coef * (coef == 0 ? 1 : coef));
				element.setLength(0);		
			}
		}
		return map;
	}

    public static void main(String[] args) throws IOException
    {
    
     
        Scanner sc = new Scanner(System.in); 
        PrintWriter out = new PrintWriter(System.out);
        int n = sc.nextInt();
        while (n-- > 0) {
    
    
        	String equation = sc.next();
        	String[] expr = equation.split("=");
        	String[] left = expr[0].split("\\+");
        	String[] right = expr[1].split("\\+");
        	Map<String, Integer> map = new HashMap<>();
        	for (String expression : left) {
    
    
        		Map<String, Integer> subMap = handle(expression);
        		for (String key : subMap.keySet()) {
    
    
        			map.put(key, map.getOrDefault(key, 0) + subMap.get(key));
        		}
        	}
        	for (String expression : right) {
    
    
        		Map<String, Integer> subMap = handle(expression);
        		for (String key : subMap.keySet()) {
    
    
        			map.put(key, map.getOrDefault(key, 0) - subMap.get(key));
        		}
        	}
        	String ans = "Y";
        	for (String key : map.keySet()) {
    
    
        		if (map.get(key) != 0) {
    
    
        			ans = "N";
        			break;
        		}
        	}
        	out.println(ans);
        }
        out.flush();
    }
} 

class Scanner{
    
    
	private BufferedReader reader;
	private StringTokenizer st;

	public Scanner(InputStream stream){
    
    
		reader = new BufferedReader(new InputStreamReader(stream));
		st = null;
	}

	public String next(){
    
    
		while(st == null || !st.hasMoreTokens()){
    
    
			try {
    
    
				String line  = reader.readLine();
				if (line == null) return null;
				st =  new StringTokenizer(line);
			} catch (Exception e) {
    
    
				throw (new RuntimeException());
			}
		}
		return st.nextToken();
	}

	public int nextInt(){
    
    
		return Integer.parseInt(next());
	}
}