I am getting the following error while opening atcoder using Yandex..

I was solving this problem which reduces down to solving the following n variable equations :

a1x1 + a2x2 + a3x3 +.... = 1mod2
b1x1 + b2x2 + b3x3 + ... = 1mod2
..

I am aware that I have to use something on the lines of Gaussian algorithm. However simple Gauss is not giving the correct answer as it involves modular arithmetic. How do I solve such equations involving multiple mods ? Thank you :)

I was trying to solve a problem which involved covering a given arc by minimal side of a square. I came to the conclusion that I had to write the equation of the arc, however it posed a great deal of difficulty to me. Kindly help. Thank you