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Java

Posted by Hind Nabet
Hind Nabet
404 Points

ParseInt, is used to convert a String into an int. Could someone explain this --> num = Integer.parseInt(args[0]);

I just can not see where the String is being converted into an int. Isn't it an integer from the beginning of the code?

public class TowersOfHanoi {

// print out instructions for moving n discs to
// the left (if left is true) or right (if left is false)
public static void moves(int n, boolean left) {
    if (n == 0) return;
    moves(n-1, !left);
    if (left) StdOut.println(n + " left");
    else      StdOut.println(n + " right");
    moves(n-1, !left);
}

public static void main(String[] args) {
    int n = Integer.parseInt(args[0]);
    moves(n, true);
}

}

1 Answer

Seth Kroger
Seth Kroger
56,413 Points
Seth Kroger
Seth Kroger
56,413 Points

If you look at the line above, args is declared as an array of Strings. What the code is doing is taking the first word in the command line after java TowersOfHanoi and tries to convert it into a number. It uses a class method (i.e., a static method) from the built-in Integer class to do it.