```go
package main

import (
	"bufio"
	"fmt"
	"os"
)

func main() {
	in := bufio.NewReader(os.Stdin)

	var n int
	fmt.Fscan(in, &n)

	seen := make(map[string]struct{}, n)
	for i := 0; i < n; i++ {
		var species, color string
		fmt.Fscan(in, &species, &color)
		seen[species+"#"+color] = struct{}{}
	}

	fmt.Print(len(seen))
}
```