Loop Problem

I am a newbie to any kind of programming and I am trying to create a loan calculator, where I need to show the amount outstanding after each year, after I have made payments. I have worked out the subtracting the outstanding amount from the payment, but I can't stop it!!! Any help would be much appreciated. Thanks in advance.

Code:

---

int a,j,r;
        float b,c,d,g,l;
        double i,h,e,k,m,n,p;
  char f;
  /*Load Pre-Requisites*/
  printf("Principal \n\r");
        scanf("%d",&a);
        printf("months \n\r");
        scanf("%f",&c);
        printf("deposit \n\r");
  scanf("%d",&j);
        printf("APR\n\r");
        scanf("%f",&d);
  b=c/12;
  printf("Years %.1f \n\r",b);
        g=d/100;
  k=a-j;
  printf("Mortgaged amount %f \n\r",k);
        g++;
  h=pow(g,b);
  i=h*k;
  printf("The total amount payable is %.2f \n\r",i);
        e=i/c;
        printf("The minimum monthly payment is %f \n\n\r",e);
printf("Do you require a Monthly or Annual statement (M or A) \n\r");
  scanf("%d",&f);
  if(f='A')
  {
    printf("Annual Mortgage Statement: \n\n\r");
    for (l=1;l<=b;l++)
    {
      n=e*12;
      for (p=i,r=1;r=1;r++,p=p-n)
      {
      printf("Year %.0f Payments of %.2f Balance %.2f \n\r",l,n,p);
      }
    }
  }
  else if(f='M')
  {
    printf("Monthly Mortgage Statement: \n\n\r");
    for (l=1;l<=b;l++)
    {
    for (m=1;m<13;m++)
      printf("Year %.0f Month %.0f Payment %.2f Balance %.2f \n\r",l,m,e);
  }

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> int a,j,r;
> float b,c,d,g,l;
> double i,h,e,k,m,n,p;
> char f;
Pick better names - you're allowed more than 1 character for a variable name
Things like
int numOfYears;
double balance;
are much more readable.

For starters, it tells you whether the code is plausable or not simply from reading it.

> if(f='A')
> for (p=i,r=1;r=1;r++,p=p-n)
Examples of using = where == or != was probably intended.

I have tried putting == instead of =, but the program just stops.

Am I doing the right thing by using for loops? Thanks again.

Code:

---

void main()
{
        int value,deposit;
        float years,term,apr,rate,month;
        double total,step,permonth,mort,paypermonth,payperyear,balance;
  char statement;
  printf("Please enter the value of the property \n\r");
        scanf("%d",&value);
        printf("Please enter the Term (in months) of the mortgage \n\r");
        scanf("%f",&term);
        printf("Please enter your initial payment (deposit) \n\r");
  scanf("%d",&deposit);
        printf("Please enter the interest rate (APR) \n\r");
        scanf("%f",&apr);
  years=term/12;
  printf("Years %.1f \n\r",years);
        rate=apr/100;
  mort=value-deposit;
  printf("The amount to be mortgaged is %.2f \n\r",mort);
        rate++;
  step=pow(rate,years);
  total=step*mort;
  printf("The total amount payable is %.2f \n\r",total);
        permonth=total/term;
        printf("The minimum amount you need to pay each month is %.2f \n\n\r",permonth);
  /*keep a running count of payments and subtract that value from total amount to pay*/
  printf("Do you require a Monthly or Annual statement? (M or A) \n\r");
  scanf("%c",&statement);
  if(statement='A')
  {
    printf("Annual Mortgage Statement: \n\n\r");
    for (month=1;month<=years;month++)
    {
      payperyear=permonth*12;
      for (balance=total;;balance=balance-payperyear)
      {
      printf("Year %.0f Payments of %.2f Balance %.2f \n\r",month,payperyear,balance);
      }
    }
  }
  if(statement='M')
  {
    printf("Monthly Mortgage Statement: \n\n\r");
    for (month=1;month<=years;month++)
    {
    for (paypermonth=1;paypermonth<13;paypermonth++)
      printf("Year %.0f Month %.0f Payment %.2f Balance %.2f \n\r",month,paypermonth,permonth);
  }
}
}

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> if(statement='A')
Does this look like == ?

Also, main returns an int, not void

I have changed both of those, and it still isn't working correctly. Sorry, I just need some help!!!!!

Some points (marked by !!) for you to think about.

Code:

---

#include <stdio.h>
#include <math.h>/*!! missing, needed for pow*/
int/*!!not void*/ main()
{
  int value,deposit;
  float years,term,apr,rate,month;
  double total,step,permonth,mort,paypermonth,payperyear,balance;
  char statement;
  printf("Please enter the value of the property \n\r");  /*!! \r is not needed */
  scanf("%d",&value);
  printf("Please enter the Term (in months) of the mortgage \n\r");
  scanf("%f",&term);
  printf("Please enter your initial payment (deposit) \n\r");
  scanf("%d",&deposit);
  printf("Please enter the interest rate (APR) \n\r");
  scanf("%f",&apr);
  years=term/12;
  printf("Years %.1f \n\r",years);
  rate=apr/100;
  mort=value-deposit;
  printf("The amount to be mortgaged is %.2f \n\r",mort);
  rate++;
  step=pow(rate,years);
  total=step*mort;
  printf("The total amount payable is %.2f \n\r",total);
  permonth=total/term;
  printf("The minimum amount you need to pay each month is %.2f \n\n\r",permonth);
  /*keep a running count of payments and subtract that value from total amount to pay*/
  printf("Do you require a Monthly or Annual statement? (M or A) \n\r");
  /*!! another scanf victim */
  while ( getchar() != '\n' );
  scanf("%c",&statement);
  if(statement==/*!! ==, not =*/'A')
  {
    printf("Annual Mortgage Statement: \n\n\r");
    /*!! month <= years makes no sense */
    for (month=1;month<=years;month++)
    {
      payperyear=permonth*12;
      /*!! this for loop has no exit condition */
      /*!! also, do you even need a loop here for annual payments? */
      for (balance=total;;balance=balance-payperyear)
      {
        printf("Year %.0f Payments of %.2f Balance %.2f \n\r",
              month,payperyear,balance);
      }
    }
  }
  if(statement==/*!! ==, not =*/'M')
  {
    printf("Monthly Mortgage Statement: \n\n\r");
    for (month=1;month<=years;month++)
    {
      for (paypermonth=1;paypermonth<13;paypermonth++)
        /*!! foo.c:51: warning: too few arguments for format */
        /*!! meaning you have more % conversions than parameters */
        printf("Year %.0f Month %.0f Payment %.2f Balance %.2f\n\r",
              month,paypermonth,permonth);
    }
  }
  return 0;/*!! missing */
}

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