A. Remaindertime limit per test1 secondmemory limit per test256 megabytesinputstandard inputoutputstandard outputYou are given a huge decimal number consisting of n digits. It is guaranteed that this number has no leading zeros. Each digit of this number is either 0 or 1.You may perform several (possibly zero) operations with this number. During each operation you are allowed to change any digit of your number; you may change 0 to 1 or 1 to 0. It is possible that after some operation you can obtain a number with leading zeroes, but it does not matter for this problem.You are also given two integers 0 \le y < x < n. Your task is to calculate the minimum number of operations you should perform to obtain the number that has remainder 10^y modulo 10^x. In other words, the obtained number should have remainder 10^y when divided by 10^x.InputThe first line of the input contains three integers n, x, y (0 \le y < x < n \le 2 \cdot 10^5) — the length of the number and the integers x and y, respectively.The second line of the input contains one decimal number consisting of n digits, each digit of this number is either 0 or 1. It is guaranteed that the first digit of the number is 1.OutputPrint one integer — the minimum number of operations you should perform to obtain the number having remainder 10^y modulo 10^x. In other words, the obtained number should have remainder 10^y when divided by 10^x.ExamplesInput
11 5 2
11010100101
Output
1
Input
11 5 1
11010100101
Output
3
NoteIn the first example the number will be 11010100100 after performing one operation. It has remainder 100 modulo 100000.In the second example the number will be 11010100010 after performing three operations. It has remainder 10 modulo 100000.
11 5 2
11010100101

1 
['implementation', 'math', '*1100']