HDU 3555 Bomb [数位]

标签：

 3
1
50
500 

 0
1
15 

Hint

From 1 to 500, the numbers that include the sub-sequence "49" are "49","149","249","349","449","490","491","492","493","494","495","496","497","498","499", so the answer is 15.
         

Analyse:

同 “不要62”，数位模板！！

但是脑残，，，，dp没开long long；

Code：

#include<iostream>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<algorithm>
#include<vector>
#include<string>
#include<queue>
#include<deque>
#include<stack>
#include<map>
#include<set>
#define INF 0x7fffffff
#define SUP 0x80000000
#define mem(a,b) memset(a,b,sizeof(a))
using namespace std;

typedef __int64 LL;
const int N=100007;
LL dp[30][10][2];
int digit[30];

LL dfs(int pos,int pre,int en,int limit)
{
    if(pos==-1) return en;
    if(!limit&&dp[pos][pre][en]!=-1) return dp[pos][pre][en];
    int last=limit?digit[pos]:9;
    LL ret=0;
    for(int i=0;i<=last;i++)
    {
        ret+=dfs(pos-1,i,en||(pre==4&&i==9),limit&&i==last);
    }
    if(!limit) dp[pos][pre][en]=ret;
    return ret;
}

LL solve(LL x)
{
    int cnt=0;
    while(x)
    {
        digit[cnt++]=x%10;
        x/=10;
    }
    return dfs(cnt-1,0,0,1);
}

int main()
{
    int T;scanf("%d",&T);
    LL n;
    mem(dp,-1);
    while(T--)
    {
        scanf("%I64d",&n);
        printf("%I64d\n",solve(n));
    }
    return 0;
}

HDU 3555 Bomb [数位]

标签：

原文地址：http://blog.csdn.net/code_or_code/article/details/45048681