# 2526. Find Consecutive Integers from a Data Stream

## Description

For a stream of integers, implement a data structure that checks if the last k integers parsed in the stream are equal to value.

Implement the DataStream class:

• DataStream(int value, int k) Initializes the object with an empty integer stream and the two integers value and k.
• boolean consec(int num) Adds num to the stream of integers. Returns true if the last k integers are equal to value, and false otherwise. If there are less than k integers, the condition does not hold true, so returns false.

Example 1:

Input
["DataStream", "consec", "consec", "consec", "consec"]
[[4, 3], [4], [4], [4], [3]]
Output
[null, false, false, true, false]

Explanation
DataStream dataStream = new DataStream(4, 3); //value = 4, k = 3
dataStream.consec(4); // Only 1 integer is parsed, so returns False.
dataStream.consec(4); // Only 2 integers are parsed.
// Since 2 is less than k, returns False.
dataStream.consec(4); // The 3 integers parsed are all equal to value, so returns True.
dataStream.consec(3); // The last k integers parsed in the stream are [4,4,3].
// Since 3 is not equal to value, it returns False.


Constraints:

• 1 <= value, num <= 109
• 1 <= k <= 105
• At most 105 calls will be made to consec.

## Solutions

• class DataStream {
private int cnt;
private int val;
private int k;

public DataStream(int value, int k) {
val = value;
this.k = k;
}

public boolean consec(int num) {
cnt = num == val ? cnt + 1 : 0;
return cnt >= k;
}
}

/**
* Your DataStream object will be instantiated and called as such:
* DataStream obj = new DataStream(value, k);
* boolean param_1 = obj.consec(num);
*/

• class DataStream {
public:
DataStream(int value, int k) {
val = value;
this->k = k;
}

bool consec(int num) {
cnt = num == val ? cnt + 1 : 0;
return cnt >= k;
}

private:
int cnt = 0;
int val, k;
};

/**
* Your DataStream object will be instantiated and called as such:
* DataStream* obj = new DataStream(value, k);
* bool param_1 = obj->consec(num);
*/

• class DataStream:
def __init__(self, value: int, k: int):
self.val, self.k = value, k
self.cnt = 0

def consec(self, num: int) -> bool:
self.cnt = 0 if num != self.val else self.cnt + 1
return self.cnt >= self.k

# Your DataStream object will be instantiated and called as such:
# obj = DataStream(value, k)
# param_1 = obj.consec(num)


• type DataStream struct {
val, k, cnt int
}

func Constructor(value int, k int) DataStream {
return DataStream{value, k, 0}
}

func (this *DataStream) Consec(num int) bool {
if num == this.val {
this.cnt++
} else {
this.cnt = 0
}
return this.cnt >= this.k
}

/**
* Your DataStream object will be instantiated and called as such:
* obj := Constructor(value, k);
* param_1 := obj.Consec(num);
*/

• class DataStream {
private val: number;
private k: number;
private cnt: number;

constructor(value: number, k: number) {
this.val = value;
this.k = k;
this.cnt = 0;
}

consec(num: number): boolean {
this.cnt = this.val === num ? this.cnt + 1 : 0;
return this.cnt >= this.k;
}
}

/**
* Your DataStream object will be instantiated and called as such:
* var obj = new DataStream(value, k)
* var param_1 = obj.consec(num)
*/