# only_14





Given a list of ints, return true if every element is a 1 or a 4.

This exercise was taken from [codingbat.com](https://codingbat.com/prob/p186672) 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:**
```
[1, 4, 1, 4]
```
**Output:**
```
True
```
### Test 2
**Input:**
```
[1, 4, 2, 4]
```
**Output:**
```
False
```
### Test 3
**Input:**
```
[1, 1]
```
**Output:**
```
True
```
### Test 4
**Input:**
```
[4, 1]
```
**Output:**
```
True
```
### Test 5
**Input:**
```
[2]
```
**Output:**
```
False
```
### Test 6
**Input:**
```
[]
```
**Output:**
```
True
```
### Test 7
**Input:**
```
[1, 4, 1, 3]
```
**Output:**
```
False
```
### Test 8
**Input:**
```
[3, 1, 3]
```
**Output:**
```
False
```
### Test 9
**Input:**
```
[1]
```
**Output:**
```
True
```
### Test 10
**Input:**
```
[4]
```
**Output:**
```
True
```
### Test 11
**Input:**
```
[3, 4]
```
**Output:**
```
False
```
### Test 12
**Input:**
```
[1, 3, 4]
```
**Output:**
```
False
```
### Test 13
**Input:**
```
[1, 1, 1]
```
**Output:**
```
True
```
### Test 14
**Input:**
```
[1, 1, 1, 5]
```
**Output:**
```
False
```
### Test 15
**Input:**
```
[4, 1, 4, 1]
```
**Output:**
```
True
```