Prog#051: while loop-"Leap year or not" between given range

/* 
Program#51
while loop-"Leap year or not" between given range
*/

#include <stdio.h>
main(){
int a,b,c=0;
printf("\nEnter two years :");
scanf("%d %d",&a,&b);
while(a<=b){
c=a%4;
if(!c)
printf("\n Leap year:%d",a);
else
printf("\n Not Leap year:%d",a);
a=a+1;
}
}