. A common problem for compilers and text editors is determining whether the parentheses in a string are balanced and properly nested. For example, the string ((())())() contains properly nested pairs of parentheses, which the strings )()( and ()) do not. Give an algorithm that returns true if a string contains properly nested and balanced paren…

parentheses.java

//return -1: correct parentheses
//return n: Position of first offending bracket
public static int parantheses(char[] chrs){

    Stack s = new Stack();

    int i = 0;

    for(;i<chrs.length;i++){ //Checks for erroneous chars omitted
        char c = chrs[i];
        if(c == '('){
            s.push(c);
        }else{ //closing bracket
            if(s.empty() || !s.peek().equals('(')){
                return i; //Return pos of offending parantheses
            }else{
                s.pop();
            }
        }
    }
    if(!s.empty()){
        return chrs.length;
    }
    return -1; //Everything good
}