思路:
简单的数位取2表示出现过13,取1表示当前位是1,否则取0
状态:,长度为
,当前数值
的值为
,状态是
,这个状态是能保证结果唯一的
Code:
#include<iostream>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<algorithm>
#include<queue>
#include <vector>
#include<map>
#include<set>
#include<utility>
using namespace std;
typedef long long ll;
inline ll read() {
ll s = 0, w = 1;
char ch = getchar();
while (ch < 48 || ch > 57) {
if (ch == '-') w = -1;
ch = getchar();
}
while (ch >= 48 && ch <= 57)
s = (s << 1) + (s << 3) + (ch ^ 48), ch = getchar();
return s * w;
}
ll dp[11][3][13];
int digit[11];
ll dfs(int len,int pos,int sum,bool limit) {
if(!len) {
return (pos==2&&sum==0);
}
if(!limit&&dp[len][pos][sum]!=-1) return dp[len][pos][sum];
int endi=(limit?digit[len]:9);
ll ans=0;
for(int i=0,tmp;i<=endi;++i) {
if(i==1&&pos!=2) tmp=1;
else if(pos==1&&i==3||pos==2) tmp=2;
else tmp=0;
ans+=dfs(len-1,tmp,(sum*10+i)%13,limit&&i==endi);
}
if(!limit) dp[len][pos][sum]=ans;
return ans;
}
ll solve(ll x) {
int len=0;
while(x) {
digit[++len]=x%10;
x/=10;
}
return dfs(len,0,0,true);
}
int main() {
ll n;
memset(dp,-1,sizeof dp);
while(~scanf("%lld",&n)) {
printf("%lld\n",solve(n));
}
return 0;
} 
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