C program to use functions with arguments and return values

 
#include<stdio.h>
#include<conio.h>

void printline(char ch, int len);
float value(float, float, int);

void main()
{
    float principal, inrate, amount;
    int period;

    printf("Enter principla amount, interest");
    printf("rate, and period");
    scanf("%f %f %d", &principal, &inrate, &period);

    printline('*',52);

    amount=value(principal, inrate, period);

    printf("n %f t %f t %d t %f nn",principal,inrate,period,amount);
    printline('=',52);
}

void printline(char ch, int len)
{
    int i;

    for(i=1;i<=len;i++)
    {
        printf("%c",ch);
    }
    printf("n");
}

float value(float p, float r, int n)
{
    int year;
    float sum;

    sum=p;
    year=1;

    while(year<=n)
    {
        sum=sum*(1+r);
        year=year+1;
    }

    return(sum);
}

 
Enter principal amount, interest rate, and period
5000 0.12  5
**************************************************
5000.000000     0.1200000   5  8811.00000
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