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【CodeForces】A. Lucky Division

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【UVa】10298 - Power Strings

Problem  here Given two strings a and b we define a ∗ b to be their concatenation. For  example, if a = ‘abc’ and b = ‘def’ then a ∗ b = ‘abcdef’. If we think of  concatenation as multiplication, exponentiation by a non-negative integer  is defined in the normal way: a  0 = ‘’ (the empty string) and a  (n+1) =  a ∗ (a  n). Input Each test case is a line of input representing s, a string of printable characters.  The length of s will be at least 1 and will not exceed 1 million  characters. A line containing a period follows the last test case. Output For each s you should print the largest n such that s = a  n for some string  a. Sample Input abcd  aaaa  ababab  . Sample Output 1  4  3 Solution #include <iostream> #include <string> //#include <fstream> #define MAX_NUM 9999999 using namespace std ; //ifstream fin("10298.in"); //ofstream fout("10298.out"); ...
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【CodeForces】A. Helpful Maths

Problem  here Problem Xenia the beginner mathematician is a third year student at elementary school. She is now learning the addition operation. The teacher has written down the sum of multiple numbers. Pupils should calculate the sum. To make the calculation easier, the sum only contains numbers 1, 2 and 3. Still, that isn’t enough for Xenia. She is only beginning to count, so she can calculate a sum only if the summands follow in non-decreasing order. For example, she can’t calculate sum 1+3+2+1 but she can calculate sums 1+1+2 and 3+3. You’ve got the sum that was written on the board. Rearrange the summans and print the sum in such a way that Xenia can calculate the sum. Input The first line contains a non-empty string  s  — the sum Xenia needs to count. String  s  contains no spaces. It only contains digits and characters “ + “. Besides, string  s  is a correct sum of numbers 1, 2 and 3. String  s  is at most 100 char...
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