Find all pairs of integers within an array which sum to a specified value

Question

Design an algorithm to find all pairs of integers within an array which sum to a specified value.

I have tried this problem using a hash

Answer 1

#python 3.x
def sum_pairs(list_data, number):    
    list_data.sort()
    left = 0
    right = len(list_data)-1
    pairs = []
    while left < right:        
        if list_data[left]+list_data[right] == number:
            find_pairs = [list_data[left], list_data[right]]
            pairs.append(find_pairs)
            right = right-1
        elif list_data[left]+list_data[right] < number:
            left = left+1
        else:
            right = right-1
    return pairs