我的程序有问题吗？ 我似乎只得到 0.0000 作为我的答案

Question

#include <stdio.h>
void main (void)    
{
    int days, seconds;
    
    printf("Enter the no. of days: ");
    scanf("%d", &days);
    
    seconds = days*36400;
    
    if (days<0)
    {
        printf("Invalid input!");
    }
    else 
    {
        printf("It is equal to %.5f seconds", seconds);
    }
}

Answer 1

You declared seconds as an integer, so you should change %.5f to %d .

#include <stdio.h>
void main (void)
{
  int days, seconds;

  printf("Enter the no. of days: ");
  scanf("%d", &days);
  
  seconds = days*36400;
 
  if (days<0)
    {
      printf("Invalid input!");
    }
  else 
    {
      printf("It is equal to %d seconds", seconds);
    }
  
}

Answer 2

There are couple of mistakes in your code

1. Before converting days into second you need to check for valid and invalid input.
2. You have taken variables in int and printing them as floating value.

Yo can use following code to get the output you want

#include <stdio.h>

int main(void) {
    int days, seconds;

    printf("Enter the no. of days: ");
    scanf("%d", &days);
    if(days<=0){
        printf("Invalid input");
    }else{
        seconds = days * 86400;
        printf("It is equal to: %.5d Seconds", seconds);
    }
}