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# Absolute Value In C

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Hey,
I'm writing a program for a friend in Calculus. The goal is for him to be able to input a number, and have the computer return whether it is positive or negative, and its absolute value. Here is what I have so far:

printf("Please enter a number linenums:0'>/* positive.cpp* The program that gets a number and checks if it is a positive number.*It prints an appropriate message indicating if its positive or negative and also prints the*absolute value of the number.*/#include <stdio.h>#include "genlib.h"#include "simpio.h"main (){     int num1;     bool positive;     printf("This program will determine if the user inputted number is positive or negative. \n");     printf("It will also display the number's absolute value. \n");     printf("Please enter a number: \n");     num1=GetInteger ();     if (num1==0)        printf("The number %d is neither positive nor negative. \n", num1);else      if (num1>0)        {                printf("The number %d is positive and its absolute value is %d. \n", num1, num1);                positive=true;                }                else          {             printf("The number %d is negative and its absolute value is %d. \n", num1, num1);             positive=false;             }        getchar ();        return 0;        }
Obviously the line
`printf("The number %d is negative and its absolute value is %d. \n", num1, num1);`
is flawed. How do I fix it so if the number is negative it will display the correct absolute value?

Thank you.

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A function would be what you are looking for. I'm sure there's one in the standard library for it called abs which will change it to an absolute number.

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So what would the line be? Yes, there is a function called abs.Something like this:printf("The number %d is negative and its absolute value is %d. \n", num1, abs:num1);?

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The correct syntax for that line would be:printf("The number %d is negative and its absolute value is %d. \n", num1, abs(num1));also if you wanted to get the absolute value of a floating point number instead you can use fabs(variable).

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Thanks, it worked great.

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