f=lambda x:-min(x.pop(0)-max(x),x[1:]and-f(x))
for x in [1,2,3,4,5], [1,99,2,105], [99,1,99,100], [99,1,1,2,1,3], [5,4,3,3,1], [5,4,3,1], [5,2,1], [5,4,1], [55,45,20,1], [5,1], [10,7,5,1]:
print f(x)
Zj1sYW1iZGEgeDotbWluKHgucG9wKDApLW1heCh4KSx4WzE6XWFuZC1mKHgpKQoKZm9yIHggaW4gWzEsMiwzLDQsNV0sIFsxLDk5LDIsMTA1XSwgWzk5LDEsOTksMTAwXSwgWzk5LDEsMSwyLDEsM10sIFs1LDQsMywzLDFdLCBbNSw0LDMsMV0sIFs1LDIsMV0sIFs1LDQsMV0sIFs1NSw0NSwyMCwxXSwgWzUsMV0sIFsxMCw3LDUsMV06CglwcmludCBmKHgp