# xy_balance



**Requirements:**
```eval_rst
- :ref:`fundamentals:access a single character`
- :ref:`fundamentals:loop through a string (while)`
- :ref:`fundamentals:if, elif, else`

```


We'll say that a String is xy-balanced if for all the `'x'` chars in the string, there exists a `'y'` char somewhere later in the string. So `"xxy"` is balanced, but `"xyx"` is not. One `'y'` can balance multiple `'x'`s. Output `True` if the given string is xy-balanced. Output `False` otherwise.

This exercise was taken from [codingbat.com](https://codingbat.com/prob/p134250) and has been adapted for the Python language. There are many great programming exercises there, but the majority are created for Java.






### Test 1
**Input:**
```
'aaxbby'
```
**Output:**
```
True
```
### Test 2
**Input:**
```
'aaxbb'
```
**Output:**
```
False
```
### Test 3
**Input:**
```
'yaaxbb'
```
**Output:**
```
False
```
### Test 4
**Input:**
```
'yaaxbby'
```
**Output:**
```
True
```
### Test 5
**Input:**
```
'xaxxbby'
```
**Output:**
```
True
```
### Test 6
**Input:**
```
'xaxxbbyx'
```
**Output:**
```
False
```
### Test 7
**Input:**
```
'xxbxy'
```
**Output:**
```
True
```
### Test 8
**Input:**
```
'xxbx'
```
**Output:**
```
False
```
### Test 9
**Input:**
```
'bbb'
```
**Output:**
```
True
```
### Test 10
**Input:**
```
'bxbb'
```
**Output:**
```
False
```
### Test 11
**Input:**
```
'bxyb'
```
**Output:**
```
True
```
### Test 12
**Input:**
```
'xy'
```
**Output:**
```
True
```
### Test 13
**Input:**
```
'y'
```
**Output:**
```
True
```
### Test 14
**Input:**
```
'x'
```
**Output:**
```
False
```
### Test 15
**Input:**
```
''
```
**Output:**
```
True
```
### Test 16
**Input:**
```
'yxyxyxyx'
```
**Output:**
```
False
```
### Test 17
**Input:**
```
'yxyxyxyxy'
```
**Output:**
```
True
```
### Test 18
**Input:**
```
'12xabxxydxyxyzz'
```
**Output:**
```
True
```