Question

I need to create a function that can takes a list of tuples and a number. Example:
if the list of tuples is [(2,5),(8,9),(11,19),(22,43),(47,50)], and the number is 14, the it should return 18.
The reason for this is at number 13 in the list 2,3,4,5,8,9,11,12,13,14,15,16,17,18,19... is 18 if all numbers are included:

1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18.

I now have:

def converting(tuples,index):
    values = [] #I will get [(2,3,4,5,6),(8,9),(11,12,13,14,15,16,17,18,19),(22,..,43),(47,48,49,50)]
    for tuple in tuples: 
        tupleValues = range(tuple[0], tuple[1]+1)
        values.extend(tupleValues)  #ex(2,3,4,5,6)
    if index <= len(values): #If 14 in the example is lower than len of the list, eg 42
        return values[index-1] #return value of 14-1, which is 16?
print converting(14,[(2,5),(8,9),(11,19),(22,43),(47,50)])

When I print this I get the message:
for tuple in tuples:
TypeError: ‘int’ object is not iterable

Answer 1

If I understand the problem correctly, you have a sequence of intervals and you need to extract the n-th number from those intervals. Here is a different solution regarding the algorithm used. Just count all the missing numbers from your interval sequence and add it to your value:

tuples = [(2,5),(8,9),(11,19),(22,43),(47,50)]
#tuples = [(2,7),(9,14),(17,20)]

def result(tuple, value):
    start = tuples[0][0] - 1
    for idx in range(len(tuples) - 1):
        if tuples[idx][1] >= value + start:
            break
        start = start + (tuples[idx+1][0] - tuples[idx][1] - 1)  
    return value + start  

for i in range(1, 16):
    print str(i) + ' ' + str(result(tuples, i))