hdu3555 Bomb 简单数位dp

水题，注意一定要用__int64

#include <iostream>
#include <cstdio>
#include <cstring>
#define ll __int64
using namespace std;
int t;
ll n;
ll dp[21][3];
void init(){
    memset(dp,0,sizeof dp);
    dp[0][1]=1;
    for(int i=1;i<=20;i++){
       dp[i][0]=dp[i-1][0]+dp[i-1][1];
       dp[i][1]=dp[i-1][0]*8+dp[i-1][1]*9;
       dp[i][2]=dp[i-1][0]+dp[i-1][2]*10;
    }
}
ll solve(ll n){
    int c[22],ct=0;
    memset(c,0,sizeof c);
    ll nn=n;
    while(n) c[ct++]=n%10,n/=10;
    ll ret=0;
    for(int i=ct-1;i>=0;i--){
        if(c[i]>=5) ret+=(ll)(c[i]-1)*(dp[i][0]+dp[i][1])+dp[i][1];
        else ret+=(ll)c[i]*(dp[i][0]+dp[i][1]);
        if(i+1<ct&&c[i]==9&&c[i+1]==4) break;
    }
    return nn-ret;
}
int main(){
    scanf("%d",&t);
    init();
    while(t--){
        scanf("%I64d",&n);
        cout<<solve(n+1)-solve(1)<<endl;
    }
    return 0;
}