#!/usr/bin/env python3
import timeit
def f():
buf = b""
for i in range(102400):
buf += b'c'
return buf
def g():
buf = bytearray()
for i in range(102400):
buf.append(b'c'[0])
return bytes(buf)
if __name__ == "__main__":
print(timeit.repeat(f, number=2))
print(timeit.repeat(g, number=2))
IyEvdXNyL2Jpbi9lbnYgcHl0aG9uMwoKaW1wb3J0IHRpbWVpdAoKZGVmIGYoKToKICAgIGJ1ZiA9IGIiIgoKICAgIGZvciBpIGluIHJhbmdlKDEwMjQwMCk6CiAgICAgICAgYnVmICs9IGInYycKCiAgICByZXR1cm4gYnVmCgpkZWYgZygpOgogICAgYnVmID0gYnl0ZWFycmF5KCkKCiAgICBmb3IgaSBpbiByYW5nZSgxMDI0MDApOgogICAgICAgIGJ1Zi5hcHBlbmQoYidjJ1swXSkKCiAgICByZXR1cm4gYnl0ZXMoYnVmKQoKaWYgX19uYW1lX18gPT0gIl9fbWFpbl9fIjoKICAgIHByaW50KHRpbWVpdC5yZXBlYXQoZiwgbnVtYmVyPTIpKQogICAgcHJpbnQodGltZWl0LnJlcGVhdChnLCBudW1iZXI9Mikp