**Problem Statement:**

A binary string is monotone increasing if it consists of some number of 0's (possibly none), followed by some number of 1's (also possibly none).

You are given a binary string s. You can flip s[i] changing it from 0 to 1 or from 1 to 0.

Return the minimum number of flips to make s monotone increasing.

**Example 1:**

**Input:** s = "00110"

**Output:** 1

**Explanation:** We flip the last digit to get 00111.

**Example 2:**

**Input:** s = "010110"

**Output:** 2

**Explanation:** We flip to get 011111, or alternatively 000111.

**Example 3:**

**Input:** s = "00011000"

**Output:** 2

**Explanation:** We flip to get 00000000.

**Constraints:**

- 1 <= s.length <= 105
- s[i] is either '0' or '1'.

**Solution:**

**Code:**

```
class Solution {
public int minFlipsMonoIncr(String s) {
int n = s.length();
int flipCount = 0;
int oneCount = 0;
for (int i = 0; i < n; i++) {
if (s.charAt(i) == '0') {
if (oneCount == 0)
continue;
flipCount++;
} else
oneCount++;
if (oneCount < flipCount)
flipCount = oneCount;
}
return flipCount;
}
}
```

**Time Complexity:**

O(N)

**Space Complexity:**

O(1)

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