hdu3555

maksyuki 发表于 oj 分类,标签:
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Bomb

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

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.

Author

fatboy_cw@WHU

Source

2010 ACM-ICPC Multi-University Training Contest(12)——Host by WHU

 

题目类型:数位DP

算法分析:dp[i][0]表示长度为i不含有49的数字的个数,dp[i][1]表示长度为i不含有49且高位数字为9的数字的个数,dp[i][2]表示长度为i含有49的数字的个数。状态转移方程为dp[i][0] = dp[i-1][0] * 10 - dp[i-1][1]; dp[i][1] = dp[i-1][2]; dp[i][2] = dp[i-1][2] * 10 + dp[i-1][1],初始条件为dp[0][0] = 1,最后对于每个读入的数字从高位开始计算:先加上当前位乘上低位含有49的数字的个数。然后判断此时49是否曾经出现过,若出现过,则累加当前位乘上低位不含有49的数字的个数。若此时最高位的值大于4,则还要加上低位不含有49且最高位数字为9的个数,最后再判断当前位和高一位的值是否能够组成49,若可以,则把标志置为true