#include <stdio.h>

int main()
{
	int ch,R,G,B,dig,white,black,pixelgray;
	dig=0;
	R=0;
	G=0;
	B=0;
	white=0;
	black=1;


	printf("Enter number:");
	while((ch=getchar()) !='\n'&& ch !=EOF)
	{
		if(ch>='0'&& ch<='9')
		dig++;
		R=(10*R)+(ch-'0');

	}
	printf("R = %d\n", R);

	printf("Enter number:");
	while((ch=getchar()) !='\n'&& ch !=EOF)
	{
		if(ch>='0'&& ch<='9')
		dig++;
		G=(10*G)+(ch-'0');

	}
	printf("G= %d\n",G);

	printf("Enter number:");
	while((ch=getchar()) !='\n'&& ch !=EOF)
	{
		if(ch>='0'&& ch<='9')
		dig++;
		B=(10*B)+(ch-'0');

	}
	printf("B= %d\n",B);

	pixelgray=((0.299*R)+(0.587*G)+(0.114*B));
	printf("the color of grey pixel is %d",pixelgray);
}