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;
 }