// 基础练习 十进制转十六进制
#include <stdio.h>
#include <string.h>
int main()
{
	int i = 0, nDec = 0, temp = 0;
	char strHex[12];
	scanf("%d",&nDec);
	if (nDec != 0)
	{
		while (nDec)
		{
			temp = nDec%16;
			switch(temp)
			{
			case 10: strHex[i] = 'A'; break;
			case 11: strHex[i] = 'B'; break;
			case 12: strHex[i] = 'C'; break;
			case 13: strHex[i] = 'D'; break;
			case 14: strHex[i] = 'E'; break;
			case 15: strHex[i] = 'F'; break;
			default: strHex[i] = (temp+'0'); break;
			}
			++i;
			nDec /= 16;
		}
		strHex[i] = '\0';
		temp = strlen(strHex)-1;
		
		for (i = temp; i >= 0; --i)
			printf("%c",strHex[i]);
	}
	else
		printf("0");

	return 0;
}