Karthik Naidu must be new here...
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Products Algorithm 
Clock Works  Google Interview Question
If its quarter past 3 then minute hand is pointing at 3 but hour hand has slightly moved forward .hour hand grazes 30 degrees for every 1 hr(60 min) . so hour hand moves 7.5 degree for every 15 min.hence angle between hour and minute hand is 7.5  0=7.5 degrees. context 
Products Algorithm
Algorithm> 1)find the product of all elements in the array .O(n). 2)Run a loop through all elements and divide the product with that number and store in another array. >Complexity = O(n+n)=O(2n)=>O(n). int i,j,prod=1; for(i=0;i<N;i++) { prod*=A[i]; //O(n) } for(i=0;i<N;i++) { O[i]=prod/A[i]; //O(n) } context 