2014 Multi-University Training Contest 1/HDU4861_Couple doubi(數論/規律)

解題報告 兩人輪流取球，大的人贏，，， 貼官方題解，，，反正我看不懂，，，先留著理解 關於費馬小定理 關於原根
找規律找到的，，，sad，，， 很容易找到循環節為p-1，每一個循環節中有一個非零的球，所以只要判斷有多少完整循環節，在判斷奇偶，，，

#include 
#include 
#include 
#include 

using namespace std;

int main()
{
    int k,p,i,j;
    while(scanf("%d%d",&k,&p)!=EOF){
        int q=k/(p-1);
        if(q%2==0)
            printf("NO\n");
        else printf("YES\n");
    }
    return 0;
}

Couple doubi

Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 145 Accepted Submission(s): 122


Problem Description DouBiXp has a girlfriend named DouBiNan.One day they felt very boring and decided to play some games. The rule of this game is as following. There are k balls on the desk. Every ball has a value and the value of ith (i=1,2,...,k) ball is 1^i+2^i+...+(p-1)^i (mod p). Number p is a prime number that is chosen by DouBiXp and his girlfriend. And then they take balls in turn and DouBiNan first. After all the balls are token, they compare the sum of values with the other ,and the person who get larger sum will win the game. You should print “YES” if DouBiNan will win the game. Otherwise you should print “NO”.
Input Multiply Test Cases.
In the first line there are two Integers k and p(1
Output For each line, output an integer, as described above.
Sample Input

2 3
20 3

Sample Output

YES
NO

Source 2014 Multi-University Training Contest 1