# Minimum steps to remove substring 010 from a binary string in C++

## Problem statement

Given a binary string, the task is to count the minimum steps to remove substring 010 from this binary string

## Example

If input string is 010010 then 2 steps are required

• Convert first 0 to 1. Now string becomes 110010
• Convert last 0 to 1. Now final string becomes 110011

## Algorithm

1. Iterate the string from index 0 sto n-2
2. If in binary string has consecutive three characters ‘0’, ‘1’, ‘0’ then any one character can be changed
Increase the loop counter by 2

## Example

Live Demo

#include <bits/stdc++.h>
using namespace std;
int getMinSteps(string str) {
int cnt = 0;
for (int i = 0; i < str.length() - 2; ++i) {
if (str[i] == '0' && str[i + 1] == '1' && str[i+ 2] == '0') {
++cnt;
i += 2;
}
}
return cnt;
}
int main() {
string str = "010010";
cout << "Minimum required steps = " << getMinSteps(str)
<< endl;
return 0;
}

When you compile and execute above program. It generates following output

## Output

Minimum required steps = 2