Points: 119

Tags: crypto 

Poll rating:

Your friend has been captured by some country's secret services and is being held in a prison. Having reached the prison, you realise there is a code there that you need to break. The enemies have been kind enough to leave a large file containing 3 numbers on each line and the following message for you: "Start with a list of 10^7 zeros and for every line containing a,b,c separated by a space in the given file, add c modulo 10 to every number in your list between indices a and b (a included only). Indices start at 1 in the list. At the end, compute the product modulo 999999937 of the nonzero digits in your list and you will obtain the password needed to free your friend". The problem is that your friend needs medication within the next 3 days so can you break the password soon enough?

Flag Format: HackTM{CODE}

Challenge Files: https://drive.google.com/file/d/1CNwGf_lKq8wHA8qYQJFkqP5HCybmYBel/view

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