ordovician

mod(A, C) == r

# then

mod(A + k*C, C) == r

# so if

mod(A, C) == mod(B, C)

ordovician

#! /usr/bin/env ruby

if ARGV.empty?
    puts "Usage: git-change-history base [new-branch-name]"
    puts "  a list of SHA-1 for commits are given on STDIN. These are commits are added onto base" 
    puts "Example:"     
    puts "  git log --pretty=\"%H\" master | git-change-history.rb base mynewbranch"
    puts ""
    puts "Use 'git log --pretty=\"%H %s\"' to test if you have the right SHA-1 commit hashes listed"
    exit