"use strict"
function main(arg) {
    let s = arg.trim().split("\n")
    s.shift()
    let data = {}
    for (let i = 0; i < s.length; i++) {
        data[s[i]] = 1
    }
    console.log(Object.keys(data).length)
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));