Simple solution in Python
def main():(a, b ,c) = map(int, raw_input().split(" "))t = a + b + cfinalList = {}voterId = 0while t > 0:voterId = int(raw_input())if voterId in finalList:finalList[voterId] +=1else:finalList[voterId] = 1;t -= 1keys = finalList.keys()keys.sort()li = []for i in keys:if finalList[i] > 1:li.append(i)print len(li)
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