Question

1. what is the output for y?

y = 0
for i in range(0, 10):
y += i
print(y)
10
0
45
0
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
10

Explanation:

Step1: Understand range function

The range(0, 10) generates a sequence of numbers from 0 to 9 (not including 10).

Step2: Analyze loop operation

The loop y += i accumulates the values of i in each iteration. So we need to sum 0 + 1+ 2 + 3+ 4+ 5+ 6+ 7+ 8+ 9.

Step3: Use sum formula

The sum of an arithmetic - series $S_n=\frac{n(a_1 + a_n)}{2}$, where $n = 10$, $a_1=0$, $a_n = 9$. So $S=\frac{10\times(0 + 9)}{2}=45$.

Answer:

C. 45