Thread: Writing your own functions

  1. #1
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    Writing your own functions

    Alright everyone check this out I'm a first year programming student and were in the chapter where we are required to write our own functions. Well the book we have is kind enough to give us functions with one variable
    example.#include <stdio.h>


    double tempvert(double);

    int main()

    {
    int count;
    double fahren;
    for (count = 1; count <= 4; ++count)
    {
    printf("enter a temparature\n");
    scanf("%lf", &fahren);
    printf("the celsius equivilent is %6.2lf\n", tempvert(fahren) );
    }
    return 0;
    }
    double tempvert(double fahren)
    {
    return ( (5.0 / 9.0 * (fahren - 32) ));
    }

    but unfortunatley they neglect to give us any examples of writing your own function which would contain two variables. So basically I've been left out to dry by the book. I tried working it out logically and it just isn't making any sense does anyone out there have an example using two variable prewritten functions

  2. #2
    Registered User Vber's Avatar
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    >>but unfortunatley they neglect to give us any examples of writing your own function which would contain two variables

    you mean a function that will receive as parameter two variables? well, it's easy... look at the prototype, this function will receive 2 integers, and return their sum.

    Code:
    int add (int a, int b) {
        return (a+b);
    }

  3. #3
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    exactly

    Thats exactly what I'm talkin about the only problem is now I just need to see one simple program that adds or subtracts two numbers utilizing a user written function and I'm homefree

  4. #4
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    Well not caring about negative numbers and such, what about

    Code:
    #include <stdio.h>
    
    int getSum(int a, int b)
    {
       return a+b;
    }
    
    int getDif(int c, int d)
    {
       return c-d;
    }
    
    int main()
    {
       printf("3+5 = %d\n", getSum(3,5));
       printf("3-5 = %d\n", getDif(3,5));
       
       return 0;
    }
    I haven't used a compiler in ages, so please be gentle as I try to reacclimate myself. :P

  5. #5
    Registered User Vber's Avatar
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    Originally posted by Vber
    >>but unfortunatley they neglect to give us any examples of writing your own function which would contain two variables

    you mean a function that will receive as parameter two variables? well, it's easy... look at the prototype, this function will receive 2 integers, and return their sum.

    Code:
    int add (int a, int b) {
        return (a+b);
    }
    Code:
    #include <stdio.h>
    
    int add (int a, int b) {
        return (a+b);
    }
    
    int main(void) {
        printf("The sum of 4 and 5 is %d\n",4,5,add(4,5));
        return 0;
    }

  6. #6
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    I've almost got it

    Thats exactly what I'm talking about, how about one with two scanf statement

  7. #7
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    Homework is fun.

    Code:
    #include <stdio.h>
    
    int getSum(int a, int b)
    {
       return a+b;
    }
    
    int getDif(int c, int d)
    {
       return c-d;
    }
    
    int main()
    {
       int n1, n2;
    
       printf("Enter num1: ");
       scanf("%d", &n1);
    
       printf("Enter num2: ");
       scanf("%d", &n2);
    
       printf("%d + %d = %d\n", n1, n2, getSum(n1, n2));
       printf("%d - %d = %d\n", n1, n2, getDif(n1, n2));
       
       return 0;
    }
    I haven't used a compiler in ages, so please be gentle as I try to reacclimate myself. :P

  8. #8
    Registered User Vber's Avatar
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    Re: I've almost got it

    Originally posted by drdodirty2002
    Thats exactly what I'm talking about, how about one with two scanf statement
    how about you do your own-homework? bahh doing homework for other people it's not fun.

  9. #9
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    I wish

    I wish this answered my homework but unfortunatley the question that I have for my homework is alot more complex than that

  10. #10
    Registered User Vber's Avatar
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    you asked something, we answered, post your code and the question, and we'll try to help you to complete the code.

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