ll@N,@M,@A[N],a,t;sort(A,A+N);a=t=sum[i,0,M-1]((A[i+1]-A[i])**2);REP(j,1,N-M+1)a<?=t+=(A[M+j-1]-A[M+j-2])**2-(A[j]-A[j-1])**2;wt(a);