Question

C语言的题目不会做啊

Write a function bool parenthesis(char str[]) that takes in a string containing parentheses(括号的意思), and determines if the parentheses are balanced. A string of parentheses is balanced if every parenthesis is closed in the reverse order that it is opened. Note that '(' is an open parenthesis and ')' is a closing parenthesis. For example, the string "(()()(()()))" is balanced, but the strings "(()))" and ")(" are not. Your function should ignore all characters except for the following: '(' and ')'. If the string is balanced, your function should return true; otherwise, it should return false

Answer 1

#include <stdio.h>
#include <stdlib.h>

/* run this program using the console pauser or add your own getch, system("pause") or input loop */

unsigned int balance(const char* str)
{
	int flags=0;
	while( *str != '\0' ){
		if( flags > 0 ) return 0; 
		if( *str == ')' ) flags++;
		else if( *str == '(' ) flags--;
		else ;
		str++;
	}
	if( flags != 0 ) return 0;
	return 1; 
} 

int main(int argc, char *argv[]) {
	char *str1="(()()(()()))";
	char *str2=")(";
	int err1=balance(str1);
	int err2=balance(str2);
	printf("%d,%d\n",err1,err2);
	system("pause");
	return 0;
}