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Given an integer, k, and an array of integers, a, count the number of pairs of integers in a that sum to k. Complete the countPairs function in the editor below. It has two parameters: 1. An integer, k, denoting the desired sum 2. An array of integers, a, denoting the values to examine More points will be awarded for solutions that can handle larger inputs within a set period of time i.e. code with a faster run-time complexity. The locked stub code in the editor reads the following input from stdin and passes it to the function: The first line contains an integer, k, denoting the desired sum. The second line contains an integer, n, denoting the size of the array, a. Each line i of the n subsequent lines (where 0 lessthanorequalto i
Expert Answer
This program requires nested loop inorder to find the pairs so complexity will be On2.
Please find below the solution and attached output:
Note : while pasting the code intendation (spacing) might be ommited as it is chegg limitation so please refer the attached code screenshot :
save below code as pair.py or any name needed please take care of itendation (spacing) as per python standard.
def find_pair(k,a):
“””
This program will find the
number of pair equalivalent to sum k
“””
#initialize count variable with 0
count=0
#nested looping through array a
for i in range(0,len(a)):
for j in range(i+1,len(a)):
#if equal to sum
if a[i] + a[j] == k:
#uncomment below line if u want to seek pair with its value
#print(“Pair is {“+str(a[i])+”, “+str(a[j])+”}”)
#increasing the count
count = count + 1
return count
#end of function
#empty list / array
a=[]
#asking sum
k= int(input(“Enter the value of k (desired sum) : “))
#askinh no of elements in array
n=int(input(“Enter an no of elements in array : “))
#using loop scanning no in array
for i in range(0,n):
a.append(int(input()))
if __name__ == “__main__”:
#finding pair by calling function
no_of_pairs = find_pair(k,a);
print(“nNo of pairs : “+str(no_of_pairs))
#Code screenshot:
#Code Output:
p
