n,d,k,*x=$<.read.split.map &:to_i
y=(0...n-d).flat_map{|i|(i+1..i+d).map{|j|[x[j]-x[i],-i,-j]}}.max
if y[0]<1
 p 0
else
 p y[0]*k
 print -y[1],' ',-y[2]
end