hdu 3652 (counting)

#include <utility>#include <algorithm>#include <string>#include <cstring>#include <cstdio>#include <iostream>#include <iomanip>#include <set>#include <vector>#include <cmath>#include <queue>#include <bitset>#include <map>#include <iterator>using namespace std;#define clr(a,v) memset(a,v,sizeof(a))#define lson l,m,rt<<1#define rson m+1,r,rt<<1|1const int INF = 0x7f7f7f7f;const int maxn = 211111;const double pi = acos(-1.0);const double eps = 1e-10;const int mod = 777777777;typedef long long ll;typedef pair<int, int> pii;typedef vector<int> VI;typedef vector<VI> VVI;typedef vector<VVI> VVVI;int dp[13][13][13];int d[13];int dfs(int pos,int pre,int have,bool doing){if(pos<0)return have==2&&pre==0;if(!doing&&dp[pos][pre][have]!=-1)return dp[pos][pre][have];int end=doing?d[pos]:9,ans=0;for(int i=0;i<=end;++i){int npre=(pre*10+i)%13;int nhave=have;if(have==1&&i==3)nhave=2;else if(have<2)nhave=(i==1);ans+=dfs(pos-1,npre,nhave,doing&&i==end);}if(!doing)dp[pos][pre][have]=ans;return ans;}int cal(int n){int cnt=0;while(n){d[cnt++]=n%10;n/=10;}return dfs(cnt-1,0,0,true);}int main() {memset(dp,-1,sizeof(dp));ios::sync_with_stdio(false);int n;while(cin>>n){cout<<cal(n)<<endl;}return 0;}