FAFU OJ AC

A C

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Description:

      Are you excited when you see the title "AC" ? If the answer is YES , AC it ; 

You must learn these two combination formulas in the school . If you have forgotten it , see the picture. 




Now I will give you n and m , and your task is to calculate the answer .

Input:

In the first line , there is a integer T indicates the number of test cases. Then T cases follows in the T lines. Each case contains a character 'A' or 'C', two integers represent n and m. (1<=n,m<=10)

Output:

For each case , if the character is 'A' , calculate A(m,n),and if the character is 'C' , calculate C(m,n). And print the answer in a single line.

Sample Input:

2

A 10 10

C 4 2

Sample Output:

3628800

6

Source:

#include<stdio.h>
int A(int n,int m)
{
    int i,sum=1;
    for(i=n;i>=n-m+1;i--)
    {
        sum*=i;
    }    
    return sum;
}
int C(int n,int m)
{
    return A(n,m)/A(m,m);
}
int main()
{
    int T,n,m;
    char ch;
    scanf("%d",&T);
    getchar();
    while(T--)
    {
        scanf("%c%d%d",&ch,&n,&m);
        if(ch=='A')
            printf("%d\n",A(n,m));
        else
            printf("%d\n",C(n,m));
        getchar();
    }
    return 0;    
}

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