HDU-1792: A New Change Problem

数论

Description

Now given two kinds of coins A and B,which satisfy that GCD(A,B)=1.Here you can assume that there are enough coins for both kinds.Please calculate the maximal value that you cannot pay and the total number that you cannot pay.

Input

The input will consist of a series of pairs of integers A and B, separated by a space, one pair of integers per line.

Output

For each pair of input integers A and B you should output the the maximal value that you cannot pay and the total number that you cannot pay, and with one line of output for each line in input.

Sample Input

2 3
3 4

Sample Output

1 1
5 3

题意：输入两个互质的数A，B，求最大不能表示的数，和不能表示的数的个数。

分析：数学问题，不会推导。
个数：（A-1）*（B-1）/2
最大不能表示的数：A*B-A-B

• 完整代码：

#include<stdio.h>
int main()
{
    int a,b;
    while(scanf("%d%d",&a,&b)!=EOF)
    {
        printf("%d %d\n",a*b-a-b,(a-1)*(b-1)/2);
    }
    return 0;
}