https://vjudge.net/problem/Gym-100283F 题意: 1 1 2 1 1 2 3 2 1 1 2 3 4 3 2 1 .... 给出这样的序列,然后给出一个n,计算从1+1+2+1+1+2+3...加到大于等于n至少需要多少个数. 思路: 二分法. 每一行的总和为,所以第i行之前的数总和为,所以我们可以可以利用二分法,确定第i行(第i+1行的总和大于了n).接下来我们继续在第i+1行进行二分. #include<iostream> #include<alg…

数学公式: n^2的前n项和n(n+1)(2*n+1)/6,用二分进行查找: 算出层数后继续二分查找位于这一层的哪一位,也可以推出相应公式 #include <iostream> #include <cstdio> #include <cstring> #include <algorithm> using namespace std; typedef long long ll; ll f(ll n) //a(n)=n^2的前n项和公式 { return n*…

题目链接:http://codeforces.com/gym/100283/problem/F F. Bakkar In The Army time limit per test 2 seconds memory limit per test 256 megabytes input army.in output standard output Bakkar is now a senior college student studying computer science. And as many…

http://codeforces.com/gym/100283/problem/F 思路是二分第几行,二分出来的行是总和 >= n的,那么第k - 1行一定要选,那么再在第k行中二分那一列. #include <cstdio> #include <cstdlib> #include <cstring> #include <cmath> #include <algorithm> #include <assert.h> #defi…

 Gym 101047M Removing coins in Kem Kadrãn Time Limit:2000MS     Memory Limit:65536KB     64bit IO Format:%I64d & %I64u Practice Description standard input/output Andréh and his friend Andréas are board-game aficionados. They know many of their friend…

 Gym 101047K Training with Phuket's larvae Time Limit:2000MS     Memory Limit:65536KB     64bit IO Format:%I64d & %I64u Practice Description standard input/output Thai cuisine is known for combining seasonings so that every dish has flavors that are…

Gym 101047E Escape from Ayutthaya Time Limit:2000MS     Memory Limit:65536KB     64bit IO Format:%I64d & %I64u  Practice  Description standard input/output Ayutthaya was one of the first kingdoms in Thailand, spanning since its foundation in 1350 to…

 Gym 101047B  Renzo and the palindromic decoration Time Limit:2000MS     Memory Limit:65536KB     64bit IO Format:%I64d & %I64u Practice Description standard input/output At the ruins of Wat Phra Si Sanphet (วดพระศรสรรเพชญ), one can find famous inscr…

Saruman's Army Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 8477   Accepted: 4317 Description Saruman the White must lead his army along a straight path from Isengard to Helm’s Deep. To keep track of his forces, Saruman distributes se…

http://poj.org/problem?id=3069 Saruman the White must lead his army along a straight path from Isengard to Helm’s Deep. To keep track of his forces, Saruman distributes seeing stones, known as palantirs, among the troops. Each palantir has a maximum…