include <stdio.h>

int main()
{
int mark;

printf("Enter mark : ");
scanf("%d, &mark");

if (mark >=90)
{
printf("A\n\n");
}

else if(mark >=80 && mark <90)
{
printf("B\n\n");
}
printf("Your mark is %d\n",mark);
getch ();
return 0;
}

i run it and input number and the cmd stops working plz help :(