Description If an integer is not divisible by 2 or 5, some multiple of that number in decimal notation is a sequence of only a digit. Now you are given the number and the only allowable digit, you should report the number of digits of such multiple.
For example you have to find a multiple of 3 which contains only 1’s. Then the result is 3 because is 111 (3-digit) divisible by 3. Similarly if you are finding some multiple of 7 which contains only 3’s then, the result is 6, because 333333 is divisible by 7.
Input Input starts with an integer T (≤ 300), denoting the number of test cases.
Each case will contain two integers n (0 < n ≤ 106 and n will not be divisible by 2 or 5) and the allowable digit (1 ≤ digit ≤ 9).
Output For each case, print the case number and the number of digits of such multiple. If several solutions are there; report the minimum one.
Sample Input 3 3 1 7 3 9901 1 Sample Output Case 1: 3 Case 2: 6 Case 3: 12
#include<cstdio> int main() { int T,nl = 0,a,b,ans,cut; scanf("%d",&T); while(T--) { scanf("%d %d",&a,&b); cut = 1; ans = b % a; while(ans) { ans = (ans * 10 + b) % a; cut++; } printf("Case %d: %d\n",++nl,cut); } return 0; }