给定进制下1-n每一位数的共享（Digit sum）The Preliminary Contest for ICPC Asia Shanghai 2019

题意：https://nanti.jisuanke.com/t/41422

对每一位进行找循环节规律就行了。

 #define IOS ios_base::sync_with_stdio(0); cin.tie(0);

 #include <cstdio>//sprintf islower isupper

 #include <cstdlib>//malloc  exit strcat itoa system("cls")

 #include <iostream>//pair

 #include <fstream>//freopen("C:\\Users\\13606\\Desktop\\草稿.txt","r",stdin);

 #include <bitset>

 //#include <map>

 //#include<unordered_map>

 #include <vector>

 #include <stack>

 #include <set>

 #include <string.h>//strstr substr

 #include <string>

 #include <time.h>//srand(((unsigned)time(NULL))); Seed n=rand()%10 - 0~9;

 #include <cmath>

 #include <deque>

 #include <queue>//priority_queue<int, vector<int>, greater<int> > q;//less

 #include <vector>//emplace_back

 //#include <math.h>

 //#include <windows.h>//reverse(a,a+len);// ~ ! ~ ! floor

 #include <algorithm>//sort + unique : sz=unique(b+1,b+n+1)-(b+1);+nth_element(first, nth, last, compare)

 using namespace std;//next_permutation(a+1,a+1+n);//prev_permutation

 #define rint register int

 #define fo(a,b,c) for(rint a=b;a<=c;++a)

 #define fr(a,b,c) for(rint a=b;a>=c;--a)

 #define mem(a,b) memset(a,b,sizeof(a))

 #define pr printf

 #define sc scanf

 #define ls rt<<1

 #define rs rt<<1|1

 typedef long long ll;

 void swapp(int &a,int &b);

 double fabss(double a);

 int maxx(int a,int b);

 int minn(int a,int b);

 int Del_bit_1(int n);

 int lowbit(int n);

 int abss(int a);

 const double E=2.718281828;

 const double PI=acos(-1.0);

 //const ll INF=(1LL<<60);

 const int inf=(<<);

 const double ESP=1e-;

 const int mod=(int)1e9+;

 const int N=(int)1e6+;

 int ans[][];

 ll m[]={,,,,,,,,,,};

 int geet(int n,int b)

 {

     int sum=;

     while(n>)

     {

         sum+=n%b;

         n/=b;

     }

     return sum;

 }

 ll get(ll n,ll b)

 {

     ll temp=n;

     int l=;

     while(temp>)

     {

         temp/=b;

         l++;

     }

     ll sum=;

     ll val[];

     val[l]=;

     n++;

     for(int i=l-;i>=;--i)

         val[i]=val[i+]*b;

     for(int i=;i<=l;++i)

     {

         ll LOOP=n/(val[i]*b);

         sum+=LOOP*m[b]*val[i];

         ll len=n%(val[i]*b);

         int start=;

         while(len>=val[i])

         {

             sum+=start*val[i];

             start++;

             len-=val[i];

         }

         sum+=len*start;

     }

     return sum;

 }

 int main()

 {

     int T,cont=;

     sc("%d",&T);

     while(T--)

     {

         ll n;int b;

         sc("%lld%d",&n,&b);

         for(int i=;i<=;++i)

         {

             ans[i][]=;

             for(int j=;j<=;++j)

                 ans[i][j]=ans[i][j-]*b;

         }

 //        for(int i=1;i<=100;++i)

     //        pr("%lld\n",get(i,2));

         pr("Case #%d: %lld\n",++cont,get(n,b));

     }

     return ;

 }

 /**************************************************************************************/

 int maxx(int a,int b)

 {

     return a>b?a:b;

 }

 void swapp(int &a,int &b)

 {

     a^=b^=a^=b;

 }

 int lowbit(int n)

 {

     return n&(-n);

 }

 int Del_bit_1(int n)

 {

     return n&(n-);

 }

 int abss(int a)

 {

     return a>?a:-a;

 }

 double fabss(double a)

 {

     return a>?a:-a;

 }

 int minn(int a,int b)

 {

     return a<b?a:b;

 }