2 questions on codepad:

1. find second largest number in a list
2. calculate and keep track of weighted averages of each student given a list of scores on different tests. then return the max weighted average ( round down to an int if it's a float value)
   eg. input [ A: 30, B:50, C:-10, A:25,B:-6]
   output: 27
   explanation: A has highest weighted average of 27.5.