題意: \(f(i)=x\),\(x\)為最小的不能整除\(i\)的數.求\(\sum^{n}_{i=1}f(i)\ mod\ 10^9+7\). 題解:首先,\(1,2,..., ...

Great Graphs 題意 給你一個數組\(d\)，\(d[i]\)表示從節點\(1\)到其他各個節點的最短路的長度，然后你可以對這個圖進行加邊（可以是負邊），但不允許存在一個權值和為負數的回 ...

There is a river of width n">nn. The left bank of the river is cell 0">00 and the right bank is c ...

C. Neko does Maths time limit per test 1 second memory limit per test 256 megabytes input standard ...

Codeforces Round #735 (Div. 2) C. Mikasa ps:代碼最后調出來來不及交了，沒有AC，純屬口嗨 qwq 本質是找個最小的k使得n^k>m \(n > m\) 則答案為0 下面描述的n的變化量即為要找的k。 1、找到n最高的值為1且不與m ...

鏈接: https://codeforces.com/contest/1234/problem/C 題意: You are given a system of pipes. It consists of two rows, each row consists of n pipes. ...

鏈接: https://codeforces.com/contest/1241/problem/C 題意: You are an environmental activist at heart but the reality is harsh and you are just ...

Suppose you have two points 𝑝=(𝑥𝑝,𝑦𝑝)p=(xp,yp) and 𝑞=(𝑥𝑞,𝑦𝑞)q=(xq,yq). Let's denote the Ma ...