Cannot figure out why my code is not working [closed] - c

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I've been trying to figure out what is wrong with my code for days; I can't seem to find it. If statements confuse me quite a bit, so I'm thinking I messed those up, but still not sure. All I know is that I'm super stumped and would love all of the help I can get.
#include <stdio.h>
// function main begins program execution
int main(void)
{
int numberOfDays = 0;
float numberOfMiles = 0;
float milesCharge = 0;
float milesTotal = 0;
float total = 0;
float subtotal = 0;
float tax = 0;
do {
printf("%s", "How many days was car rented?\t");
scanf("%d", &numberOfDays);
} while (numberOfDays < 1 );
do {
printf("%s", "How many miles were driven?\t");
scanf("%d", &numberOfMiles);
} while (numberOfMiles > 1);
if (numberOfMiles > 1 || numberOfMiles < 200) {
milesTotal = numberOfMiles * .40;
} else {
milesTotal = numberOfMiles * .35;
}
subtotal = milesTotal + numberOfDays * 15;
tax = subtotal * .06;
total = tax + subtotal;
printf("\nSubtotal:\t\t\t$%.2f\n", subtotal);
printf("Tax Amount:\t\t\t$%.2f\n", tax);
printf("Total:\t\t\t\t$%.2f\n", total);
printf("\n");
}

Answer 1

If numberOfMiles should be of type float you have to exchange the following line
scanf("%d", &numberOfMiles);
by
scanf("%f", &numberOfMiles);
or you can set the type to int.
--
If you want to avoid an endless loop, exchange
} while (numberOfMiles > 1);
by
} while (numberOfMiles < 1);
Btw. why not allow distances that are shorter than a mile?
e.g. by
} while (numberOfMiles < 0);
For more specific answers, you have to be more precise.

Answer 2

Compiling your program with gcc gives the following warning:
t.c: In function ‘main’:
t.c:21:5: warning: format ‘%d’ expects argument of type ‘int *’, but argument 2 has type ‘float *’ [-Wformat=]
scanf("%d", &numberOfMiles);
^
The problem is, that scanf() will store the number entered at the location of numberOfMiles using a binary format used for int variables, but numberOfMiles is a float variable. The integer bit pattern interpreted as float will probably have a very different meaning, or even can be an illegal float value.
Changing the type of numberOfMiles from float to int fixes this problem.
You also should change the second while condition to while (numberOfMiles < 1).
I hope, this helps.
73, Mario