Luo Gu p1980 Counting Problems

Title Description

Calculate the range of 11 1 to nn all integer n, the numbers the X-(0≤x≤9) the X-(0 ≤ ≤ the X-9) the X- ( 0 ≤ the X- ≤ 9 ) there was a total of how many times? For example, in . 11 1 to . 11. 11 1 1, i.e. 1,2,3,4,5,6,7,8,9,10,111,2,3,4,5,6,7,8,9, 10, 11 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 1 0 , 1 1, numeral . 11 1 appeared 44 is four.

Input Format

22 is two integers n-, Xn, X n- , X, separated by a space between.

Output Format

11 an integer representing the xx number of times x appears.

Sample input and output

Input # 1 copy

11 1

Output # 1 copy

4 


Code 

#include <stdio.h> 
int main () { 
 int A, B, J = 0; 
 Scanf ( "% D% D", & A, & B); 
 for (int I =. 1; I <= A; I ++ ) { 
  int D = I; 
  the while (D> 0) { 
   int C D% = 10; // get the last bit of 
   d = d / 10; // remove the last        
   IF (C == B) { 
    J ++; / / is determined whether the same, then the cycle has to know the number 0 == 
   } 
  } 
 } 
 the printf ( "% D", J); 
 return 0; 
}