补题ing.... 从简单补起...
补题顺序:D - E - B(3/10)
D - Knapsack Cryptosystem
原题链接:D.Knapsack Cryptosystem
题解链接:https://www.cnblogs.com/Tianwell/p/11372748.html
E - All men are brothers
原题链接:E - All men are brothers
题解链接:https://www.cnblogs.com/Tianwell/p/11372758.html
B - Quadratic equation 2019牛客多校(二次剩余)