def solution(i, j, k):
answer = 0
for x in range(i,j+1):
for y in str(x):
if str(k) == str(y):
answer += 1
return answer
def solution(i, j, k):
answer = sum([ str(i).count(str(k)) for i in range(i,j+1)])
return answer
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def solution(i, j, k):
return sum(map(lambda v: str(v).count(str(k)), range(i, j+1)))