//演算除法时可以发现规律//某个数不能被n整除时,余数乘以10+1是下一个数整除n时倒数第二位的余数//以7为例//         ___0_      ___1__       ___15_    ___158_     __1587_      ___15873__//       7/    1    7/  11        /  111    /  1111     / 11111      /  111111//       /-----       /----7---    /--- 7-   /----7---   /---7---     /  --7----//            1            4            41        41         41            41//                       ---35-    ---35--     --35--        --35---//                       6    -----61-    ----61-       ----61--//                                     56         56            56//                                                    5          51          --51--//                                         --49--     //                                           -21-//                                        ----21--//                                             0 #include <iostream>using namespace std;int main(){    int n;    while(cin>>n)    {        if(n%5!=0)        {                int j=1;            int t=1;            while(t%n)            {                t=t%n*10+1;                j++;            }            cout<<j<<endl;        }    }    return EXIT_SUCCESS;}

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