const input = require("fs").readFileSync("/dev/stdin", "utf8")

;(input => {
 
    const lines = input.split('\n')
    const N = lines[0] - 0
    const S = lines

    let c = 0
    const m = {}
    for (let i = 1; i <= N; i++) {
        if (!m[S[i]]) {
            m[S[i]] = 1
            c++
        }
    }
    console.log(c)
 
})(input)
