[Solution] Permutation GCD solution codechef

Permutation GCD solution codechef – Chef is interested in the sum of GCDs of all prefixes of a permutation of the integers \{1, 2, \ldots, N\}{1,2,…,N}. [Solution] Permutation GCD solution codechef Formally, for a permutation P = [P_1, P_2, \ldots, P_N]P=[P1​,P2​,…,PN​] of \{1, 2, \ldots, N\}{1,2,…,N}, let us define a function F_i = \gcd(A_1, A_2, A_3, \ldots, A_i)Fi​=gcd(A1​,A2​,A3​,…,Ai​). Chef is … Read more