# Determine a mathematical expression in the parentheses matches

2010-08-19  来源：本站原创  分类：Java  人气：152

Use stack, making it fairly simple for this operation.

```package com.java.util;

import java.util.Stack;

public class MyStack {
public static boolean check(String input){
Stack<Character> stack = new Stack<Character>();
for(int i=0;i<input.length();i++){
char ch = input.charAt(i);
switch(ch){
case '{':       case '[':       case '(':
stack.push(ch);
break;
case '}':       case ']':       case ')':
if(!stack.isEmpty()){//[]](){}
char chx = stack.pop();
if(ch == '}' && chx != '{'
|| (ch == ']' && chx != '[')
|| (ch == ')' && chx != '(')){
return false;
}
}else{//[](){})
return false;
}
break;
default:
break;
}
}
if(!stack.isEmpty()){//[](){}(
return false;
}

return true;
}
public static void main(String[] args) {
System.out.println(MyStack.check(input));
}

}
```

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Use stack, making it fairly simple for this operation. package com.java.util; import java.util.Stack; public class MyStack { public static boolean check(String input){ Stack<Character> stack = new Stack<Character>(); for(int i=0;i<input.len

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