136. Erasing Edges time limit per test: 0.25 sec. memory limit per test: 4096 KB Little Johnny painted on a sheet of paper a polygon with N vertices. Then, for every edge of the polygon, he drew the middle point of the edge. After that, he went to sc…

134. Centroid time limit per test: 0.25 sec. memory limit per test: 4096 KB You are given an undirected connected graph, with N vertices and N-1 edges (a tree). You must find the centroid(s) of the tree. In order to define the centroid, some integer…

题目大意:已知一个多边形上的每条边的中点,还原出来一个多边形. 分析:因为偶数是不固定的,所以可以为任意起点,奇数只有一个,可以所有中点加减算出来第一个点,然后就是简单的向量计算点的位置了...... ================================================================================================================== #include<stdio.h> #include<str…

127. Telephone directory time limit per test: 0.25 sec. memory limit per test: 4096 KB CIA has decided to create a special telephone directory for its agents. The first 2 pages of the directory contain the name of the directory and instructions for a…

126. Boxes time limit per test: 0.25 sec. memory limit per test: 4096 KB There are two boxes. There are A balls in the first box, and B balls in the second box (0 < A + B < 2147483648). It is possible to move balls from one box to another. From one…

123. The sum time limit per test: 0.25 sec. memory limit per test: 4096 KB The Fibonacci sequence of numbers is known: F1 = 1; F2 = 1; Fn+1 = Fn + Fn-1, for n>1. You have to find S - the sum of the first K Fibonacci numbers. Input First line contains…

120. Archipelago time limit per test: 0.25 sec. memory limit per test: 4096 KB Archipelago Ber-Islands consists of N islands that are vertices of equiangular and equilateral N-gon. Islands are clockwise numerated. Coordinates of island N1 are (x1, y1…

119. Magic Pairs time limit per test: 0.5 sec. memory limit per test: 4096 KB “Prove that for any integer X and Y if 5X+4Y is divided by 23 than 3X+7Y is divided by 23 too.” The task is from city Olympiad in mathematics in Saratov, Russia for schoolc…

118. Digital Root time limit per test: 0.25 sec. memory limit per test: 4096 KB Let f(n) be a sum of digits for positive integer n. If f(n) is one-digit number then it is a digital root for n and otherwise digital root of n is equal to digital root o…

117. Counting time limit per test: 0.25 sec. memory limit per test: 4096 KB Find amount of numbers for given sequence of integer numbers such that after raising them to the M-th power they will be divided by K. Input Input consists of two lines. Ther…