LeetCode-in-Java
2648. Generate Fibonacci Sequence
Easy
Write a generator function that returns a generator object which yields the fibonacci sequence.
The fibonacci sequence is defined by the relation Xn = Xn-1 + Xn-2.
The first few numbers of the series are 0, 1, 1, 2, 3, 5, 8, 13.
Example 1:
Input: callCount = 5
Output: [0,1,1,2,3]
Explanation:
const gen = fibGenerator();
gen.next().value; // 0
gen.next().value; // 1
gen.next().value; // 1
gen.next().value; // 2
gen.next().value; // 3
Example 2:
Input: callCount = 0
Output: []
Explanation: gen.next() is never called so nothing is outputted
Constraints:
0 <= callCount <= 50
Solution
function* fibGenerator(): Generator<number, any, number> {
let first = 0
let second = 1
let value = 0
let count = 0
while (true) {
if (count <= 1) {
count++
yield value++
} else {
value = first + second
first = second
second = value
yield value
}
}
}
/*
* const gen = fibGenerator();
* gen.next().value; // 0
* gen.next().value; // 1
*/
export { fibGenerator }