hdu 3555 Bomb(数位DP，4级)

Bomb

Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 131072/65536 K (Java/Others)

Total Submission(s): 4443 Accepted Submission(s): 1538



[align=left]Problem Description[/align]
The counter-terrorists found a time bomb in the dust. But this time the terrorists improve on the time bomb. The number sequence of the time bomb counts from 1 to N. If the current number sequence includes the sub-sequence "49", the
power of the blast would add one point.

Now the counter-terrorist knows the number N. They want to know the final points of the power. Can you help them?

[align=left]Input[/align]
The first line of input consists of an integer T (1 <= T <= 10000), indicating the number of test cases. For each test case, there will be an integer N (1 <= N <= 2^63-1) as the description.

The input terminates by end of file marker.

[align=left]Output[/align]
For each test case, output an integer indicating the final points of the power.

[align=left]Sample Input[/align]

3
1
50
500

[align=left]Sample Output[/align]

0
1
15

HintFrom 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.

[align=left]Author[/align]
fatboy_cw@WHU

[align=left]Source[/align]
2010 ACM-ICPC Multi-University
Training Contest（12）——Host by WHU

[align=left]Recommend[/align]
zhouzeyong

很水的数位DP

#include<cstdio>
#include<cstring>
#include<iostream>
#define FOR(i,a,b) for(int i=a;i<=b;++i)
#define clr(f,z) memset(f,z,sizeof(f))
#define LL __int64
using namespace std;
LL dp[40][10][2];//位数，最后一个数，是否有49
int bit[40],pos;
LL DP(int pp,int ee,bool has,bool big)
{
if(pp==0)return has;
if(big&&dp[pp][ee][has]!=-1)return dp[pp][ee][has];
int kn=big?9:bit[pp];
LL ret=0;
FOR(i,0,kn)
{
ret+=DP(pp-1,i,has||(ee==4&&i==9),big||(i!=kn));
}
if(big)dp[pp][ee][has]=ret;
return ret;
}
LL get(LL x)
{ pos=0;
while(x)
{
bit[++pos]=x%10;x/=10;
}
clr(dp,-1);
return DP(pos,0,0,0);
}
int main()
{
int cas;
while(cin>>cas)
{
while(cas--)
{
LL n;
cin>>n;
cout<<get(n)<<endl;
}
}
}