warning C4244: 'function': conversion from 'time_t' to 'unsigned int', possible loss of data'

1
votes
#include <stdio.h>
#include <conio.h>
#include <stdlib.h>
#include <time.h>

// Program to generate random numbers, using an array

int main() {
int arr[50];
int i;

srand((unsigned int)time(NULL));
for (i = 0; i < 50; i++)
{
    arr[i] = rand() % 50;
    printf("arr[%d] = %d\t", i, arr[i]);
}
_getch();
return 0;

}

I'm getting this warning:

(12): warning C4244: 'function': conversion from 'time_t' to 'unsigned int', possible loss of data.

1
c
You need to include the correct header file that declares the time function. - Some programmer dude
You have other problems though, since you seem to have forgotten that array indexes are zero-based. I.e. the valid indexes of an array of 50 elements is 0 to 49 (inclusive). Not that you need an array in the code you show, really. - Some programmer dude
Hi, I wanted to have the array within the range of 1 to 50 instead of 0-49. - JK_PROGRAMMER
And the question after your edit is very different. And you forgot to change your title. Please read about how to ask good questions, as well as this question checklist. - Some programmer dude
Regarding the array, why? Especially since it means you (currently) will go out of bounds of it? - Some programmer dude

1 Answers

2
votes

srand wants an unsigned int as argument, but time returns a time_t which is a larger type than unsigned int on your platform, hence the warning possible loss of data.

In this case the warning can be ignored, because you actually just want to give a seemingly random value to srand.

To get rid of the warning you can cast the value returned by time to unsigned int:

srand((unsigned int)time(NULL));