The function returns a -1 if the elements are not out of order, otherwise it returns the index of the first element that is out of order. Explain what you do to avoid out of bounds array access.

Question

Consider the declaration
```
double a[10] = {1.2, 2.1, 3.3, 3.5, 4.5, 7.9, 5.4,
8.7, 9.9, 1.0};
```
Write a function named out_of_order that will test this array for the condition
```
a[0] <= a[1] <= a[2] <= ...
```

Answer 1

```
int out_of_order(double array[], int size)
{
for(int i=0; i < size-1; i++)
if (array[i] > array[i+1])
return i+1;
return -1;
}
```
The upper limit for index i is size-1 because we fetch a[i+1] for each i in the range of the loop. Otherwise we would fetch and compare a[size], causing erroneous results. (We don’t know what is in that location.)