Problems with scanf and or fgets program cuttoff - c

Question

I am trying to write a code that reads in a integer using scanf and then asks the user if they would like to enter another by entering "yes" or "no". I get no errors when I compile but when I run the program it asks for the number, displays it as it should, ask to continue and then promptly closes without taking any input.
int main()
{
int *data=malloc(1*sizeof(int));
if(data==NULL)
{
printf("out of memory");
exit(1);
}
char *yc="yes";
char uinput[20];
int numinput;
printf("enter a number \n");
scanf("%d",&numinput);
data[0]=numinput;
printf("you entered %d \n",numinput);
printf("would you like to enter another # ?");
fgets(uinput,sizeof(uinput),stdin);
int count=0;
int n,i;
int comp=strncmp(uinput,yc,1);
while(comp==0)
{
n=sizeof(data)/sizeof(data[0]);
count=count+1;
data=(int*)realloc(data,n+1);
printf("enter another number:\n");
scanf("%d",&numinput);
data[n+1]=numinput;
printf("the numbers are:\n");
for(i=0;i<=count;i++)
{
printf("%d\n",data[i]);
}
printf("would you like to enter another # ?");
fgets(uinput,sizeof(uinput),stdin);
}
printf("Goodbye!\n");
return(0);
}
This is what happens when I run the program
./vector_play.out
enter a number
6
you entered 6
would you like to enter another # ?Goodbye!
I am not sure why it is immediately exiting any help would be great.

Answer 1

Your problem stems from the fact that after numinput has been read using the code in
scanf("%d",&numinput);
the newline character is still left in the input stream. The call to fgets reads the newline as a complete line and returns without waiting for any further input.
You need to add a line to ignore the rest of the input stream. You can use fgets for that purpose too.
scanf("%d",&numinput);
fgets(uinput,sizeof(uinput),stdin); // Read and ignore
printf("you entered %d \n",numinput);
printf("would you like to enter another # ?");
fgets(uinput,sizeof(uinput),stdin);