55 lines
1.2 KiB
Ruby
55 lines
1.2 KiB
Ruby
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#Given an array and number K,Print the maximum value in each sub-arrays of size K
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#Time-complexity:O(nk),Auxiliary-space:O(1)
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def find_max(a,k)
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len=a.length
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return -1 if len<k
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for i in 0..len-k
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max=a[i]
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for j in i+1...i+k
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if a[j]>max
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max=a[j]
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end
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end
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print "#{max} "
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end
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return
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end
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find_max([9,1,8,2,7,3,6,4,5,15,17],4)
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#Optimized(Though the complexity is same asymptotically but the average running time is very much optimized)
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#Check if max of last k-length subarray lies in the new window if yes then just compare the max and newly added element
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def find_max(a,k)
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len=a.length
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return -1 if len<k
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max=a[0]
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max_index=0
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for i in 0..len-k
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unless max_index<i
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if a[i+k-1]>max
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max=a[i+k-1]
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max_index=i+k-1
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end
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else
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max=a[i]
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max_index=i
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for j in i...i+k
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if a[j]>max
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max=a[j]
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max_index=j
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end
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end
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end
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print "#{max} "
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end
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return
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end
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find_max([1,2,3,1,4,5,2,3,6],3)
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find_max([9,1,8,2,7,3,6,4,5,15,17],4)
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