Sum of ones

n = int(input())
n_bits = len(bin(n))-2
# print(n_bits)

table={1:1}
for i in range(2,n_bits):
    table[i] = 2*table[i-1]+2**(i-1)
# print(table)
def count_sum(x):
    # print("calling on ", x)
    if x == 1 or x== 0:
        return x
    max_2_exponent = len(bin(x))-3
    # print(max_2_exponent)
    max_pow = 2**max_2_exponent
    # print(max_pow)
    return count_sum(x-max_pow)+ (x-max_pow+1) + table[max_2_exponent]

print(count_sum(n))

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: ACCEPTED

Test 19

Verdict: ACCEPTED

Test 20

Verdict: ACCEPTED

Test 21

Verdict: ACCEPTED