Description
Warning: Not all numbers in this problem are decimal numbers!
Multiplication of natural numbers in general is a cumbersome operation. In some cases however the product can be obtained by moving the last digit to the front.
Example: 179487 * 4 = 717948
Of course this property depends on the numbersystem you use, in the above example we used the decimal representation. In base 9 we have a shorter example:
17 * 4 = 71 (base 9)
as (9 * 1 + 7) * 4 = 7 * 9 + 1
Input
The input for your program is a textfile. Each line consists of three numbers separated by a space: the base of the number system, the least significant digit of the first factor, and the second factor. This second factor is one digit only hence less than the base. The input file ends with the standard end-of-file marker.
Output
Your program determines for each input line the number of digits of the smallest first factor with the rotamultproperty. The output-file is also a textfile. Each line contains the answer for the corresponding input line.
Sample Input
10 7 4 9 7 4 17 14 12
Sample Output
6 2 4
题意:给出进制,末尾数字,乘数,求最小几位数可以满足原数乘完后等于原数的最后一位提前。例子:179487 * 4 = 717948
tip:
输入10 7 4
1 #include<iostream> 2 3 using namespace std; 4 5 int main() 6 { 7 int j,l,x; 8 while(cin>>j>>l>>x) 9 { 10 int tmp=l*x,t1,t2,i=1; 11 while(tmp!=l) 12 { 13 t1=tmp/j; 14 t2=tmp%j; 15 tmp=t2*x+t1; 16 ++i; 17 } 18 cout<<i<<endl; 19 } 20 return 0; 21 }