40 lines
734 B
Ruby
40 lines
734 B
Ruby
#Juggling Algorithm for array rotation!
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#Time complexity: O(n) , Auxiliary-Space: O(1)
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def left_rotate_array(a, d) #Input array "a" and rotation by "d" elemets
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n=a.length
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if n>0
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if d>n # if d>n ,we take modulo n
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d%=n
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end
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for i in 0...gcd(d,n)
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temp=a[i]
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j=i
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while(true)
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k=j+d
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if k>=n
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k=k-n
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end
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if k==i
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break
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end
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a[j]=a[k]
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j=k
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end
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a[j]=temp
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end
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end
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return a
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end
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def gcd(x,y)
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if y==0
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return x
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else
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return gcd(y,x%y)
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end
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end |