#sdpsgssolutions
#Dictionary
#Starter Problems 3

# Open the input and output files.
inputFile = open("dictin.txt", "r")
outputFile = open("dictout.txt", "w")

# Read the input
myInput = inputFile.readline().split()
d = int(myInput[0])
w = int(myInput[1])
entry = 1
words = 1
# Create lists which contain the words in order
iList = []
wList = []

# Write into lists for each language
while entry <= d:
	myInput = inputFile.readline().split()
	iList.append(int(myInput[0]))
	wList.append(int(myInput[1]))
	entry = entry + 1
	
# Find the pages for each question
while words <= w:
	myInput = int(inputFile.readline())
	if myInput in iList:
		a = iList.index(myInput)
		b = wList[a]
		outputFile.write(str(b)+'\n')
	else:
		outputFile.write('C?'+'\n')
	words = words + 1

# Finally, close the input/output files.
inputFile.close()
outputFile.close()