Program7.java

package assignment1;
import java.util.Stack;
public class Program7 {
}
class PtI
{

    static boolean isOperand(char x)
    {
        return (x >= 'a' && x <= 'z') ||
                (x >= 'A' && x <= 'Z');
    }
    static String getInfix(String exp)
    {
        Stack<String> s = new Stack<String>();

        for (int i = 0; i < exp.length(); i++)
        {
            if (isOperand(exp.charAt(i)))
            {
                s.push(exp.charAt(i) + "");
            }
            else
            {
                String op1 = s.peek();
                s.pop();
                String op2 = s.peek();
                s.pop();
                s.push("(" + op2 + exp.charAt(i) +
                        op1 + ")");
            }
        }
        return s.peek();
    }
    public static void main(String args[])
    {
        String exp = "ab*c+";
        System.out.println( "postfix to infix = "+getInfix(exp));
    }
}