Problem Breakdown 1. Find LCM for Each Pair: * For each unique pair (a[i], a[j]) in the array a, compute the Least Common Multiple (LCM). * The pairs include (a[i], a[i]) for each single number, as well as every combination of distinct numbers (a[i], a[j]) 2. Calculate Minimum Multiplier: * For each pair (a[i], a[j]), find the smallest integer mmm such that: LCM(a[i],a[j])×m≥k {LCM}(a[i], a[j]) * m .= k LCM(a[i],a[j])×m≥k * This product should also be a multiple of k. 3. Calculate the Cost: * For each pair, compute the cost of the smallest multiplier mmm, which is simply the value of mmm. * Sum up the costs for all pairs to get the total answer. eg: [4,5,6] k=12 ans=>3+12+2+2*(3+2+1)=29, give a complexity less than O(N2) less than 108 as n<=10**5 pairs->(4,4) ,(5,5,) ,(6,6) ,(4,5) ,(5,4) ,(5,6) ,(6,5) , (4,6), (6,4) so(lcm(5,5))=5*12=60 multiple of k leaves value of cost =12 for this pair similarly for others