int length = a.length;
int diffCount = 1; //The number of different integers

for(int i = 1; i < length; i++)
{
    int b = a[i];
    int c = a[i-1];

    if(c>b)
         throw new IllegalStateException("unsorted array");

    if(c!=b)
         diffCount++;
}
return diffCount;

diffCount += c != b;

int b = a[i];
int c = a[i-1];

if (c != b) …