Problem Description
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?
Input
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.
Output
For each test case, output an integer indicating the final points of the power.
Sample Input
3
1
50
500
Sample Output
0
1
15
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题意:给一个数字 n,其范围在 1~2^63-1 之间,求 1~n 之间含有 49 的数字个数
思路:跟 不要62(HDU-2089)很像的一道模板题,注意数据精度即可
Source Program
#include<iostream>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<algorithm>
#include<string>
#include<cstdlib>
#include<queue>
#include<set>
#include<map>
#include<stack>
#include<ctime>
#include<vector>
#define INF 0x3f3f3f3f
#define PI acos(-1.0)
#define N 31
#define MOD 10007
#define E 1e-6
typedef long long LL;
using namespace std;
int a[N];
LL dp[N][N][2];
LL dfs(int pos,int pre,int sta,bool limit)
{
if(pos==0)
{
if(sta)
return 1;
return 0;
}
if(!limit && dp[pos][pre][sta]!=-1)
return dp[pos][pre][sta];
LL temp=0;
int up=limit?a[pos]:9;
for(int i=up;i>=0;i--)
temp+=dfs(pos-1,i==4,sta||(i==9&&pre),limit&&i==up);
if(!limit)
dp[pos][pre][sta]=temp;
return temp;
}
LL solve(LL x)
{
int pos=0;
while(x)
{
a[++pos]=x%10;
x/=10;
}
return dfs(pos,0,0,true);
}
int main()
{
int t;
scanf("%d",&t);
memset(dp,-1,sizeof(dp));
while(t--)
{
LL n;
scanf("%lld",&n);
printf("%lld\n",solve(n));
}
return 0;
}