string to negative int problem

[pendulum101]

hey there first and foremost this is school related and if anyone has a problem with me asking for help then it is at their discretion whether or not to help me and if there is a problem with admin i can understand.

As far as requests go i feel that this is very simplistic and would really only aid me in a small way but i'll let you be the judge of that

my problem is that i needed to make a program that takes in a string of digits and output them as an integer. the problem that i am having is that i cannot figure out how to do this with negative numbers.

i know that it relates to unicode but ... im stuck
i convert the integer and using an IF i check if the first character is a '-' if it is i multiply by -1.

when the input is -1 i get 29 as an output. if anyone has any input that they would like to give i'd be very appreciative

Thanks in advance

[mrmatt1111]

int value = 0;

try
{
   value = Integer.parseInt(str);
}
catch(Exception e)
{
   System.out.println("This was not a number");
}

[pendulum101]

int value = 0;

try
{
   value = Integer.parseInt(str);
}
catch(Exception e)
{
   System.out.println("This was not a number");
}

its not as easy as that i have to convert every char in the string using a loop charAt() and then convert it accumulating the results oh and i can only use int.parseInt() to test it :( any other ideas?

[pbrockway2]

when the input is -1 i get 29 as an output.

Post a small self-contained compilable example that gives rise to this behaviour. (That way you avoid "helpful" advice like people saying that there must be an error on line 42...; )

[pendulum101]

Post a small self-contained compilable example that gives rise to this behaviour. (That way you avoid "helpful" advice like people saying that there must be an error on line 42...; )

public class lab2 {
  public static void main( String[] args ) {
    String input =  ( args[0] );
    int position = 1;
    int exponent = input.length() -(int) 1;
    int power = 1;
    int output = 0;
    int negative = -1;
    for( ; exponent > 0 ; exponent-- ) {
      power = power * 10;
    }
    for( position = 0 ; position < input.length() ; position++ ) {
        int digit = (int) input.charAt(position) - (int)'0';
        digit = digit * power;  
        output = output + digit;
        power = power / 10;
      }
         
    System.out.println("input = \"" + input + "\"");
    System.out.println("output = " + output );
  } 
}

The program must go to each char in sequence

[Fubarable]

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