C language: find the palindrome number whose 100-999 is a multiple of 7

#include <stdio.h>
int main()
{
    
	int i,a,c;
	for(i = 100 ; i <= 999 ; i++){
    
		a = i/100;
		c = i%10;
		if(a==c && i%7==0){
    
			printf("%5d",i);
		}
	}
	return 0;
}