Why the variable time1 becoming Zero? - c

Question

When I am getting some problem why time1 variable getting zero. right after calculation of floor.
#include <stdio.h>
#include <stdlib.h>
#include <windows.h>
int main()
{
int curfl = 0, destfl, floor;
int time1, high, speed;
high = 3;
speed = 5;
while(1)
{
printf("Currently the elevator is at floor number = %d\n", curfl);
printf("Enter the floor number between 0-25 : ");
scanf("%d", &destfl);
if(destfl > curfl)
{
floor = destfl - curfl;
/*****************************/
time1 = (floor * (high / speed)); //variable become zero here
/*****************************/
printf("Elevator will take %d second to reach %d (st, nd, rd) floor \n", time1, destfl);
while(curfl != destfl)
{
Sleep(1000 * 3 / 5);
curfl++;
printf("You are at floor number %d \n", curfl);
}
printf("Door opening \n");
Sleep(10000);
printf("Door Closed\n");
}
else if(destfl > curfl)
{
floor = curfl - destfl;
time1 = (floor * (3 / 5));
printf("Elevator will take %d second to reach %d (st, nd, rd) floor \n", time1, destfl);
while(curfl != destfl)
{
Sleep(1000 * 3 / 5);
curfl--;
printf("You are at floor number %d \n", curfl);
}
printf("Door opening \n");
Sleep(10000);
printf("Door Closed\n");
}
else{
printf("You are the same floor. Please getout from the elevator \n");
}
}
// printf("Hello world!\n");
return 0;
}

Answer 1

You are doing integer calculations. Switch to something that handles fractions.

Answer 2

You are running into integer division. When you do arithmetic on integers, and the result will also be an integer. So something like 1 / 3 = 0 in integer-land. So when you do (high / speed), the temporary result will be an integer, and if the answer is some decimal < 1, the result will be truncate simply to 0.
To fix this, you should change the code to use float or double instead int.

Answer 3

calculate time1 like follows :
int curfl = 0, destfl, floor;
int high;
float speed, time1;
................................
time1 = (floor * (high / speed));
It looks like its for an embedded device. So don't know how it supports floating point operation.
if it does not support, pickup a divide algorithm, declare a type like following :
struct myfloat{
int precision;
int exponent;
}
and then write a divide function like :
struct myfloat * divide(int a, int b) /* gives result for a/b */