function main(input) {
	const args = input.split('\n');
  	const N = parseInt(args[0], 10);
  	let arr = args.slice(1, args.length);
  	
  	const another_arr = [...new Set(arr)];
  
  	console.log(another_arr.length);
}

main(require('fs').readFileSync('/dev/stdin', 'utf8'));