"use strict";

const main = arg => {
    const input = arg.trim().split("\n");
    const x = BigInt(input[0])
    let m = BigInt(100)
    let y = 0
    while(m < x){
        m = BigInt(Math.trunc(Number(m) * 1.01))
        y++
    }
    console.log(y)
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));  