How to get all keys with maximum value no built in-CodePudding

I have a task to get keys with maximum values. What I have now works except for when the max appears more than once. So, for example {a:2,b:1,c:2} right now this returns just a but I need it to return both a and c. I know there are question like this already but I need it to NOT have any built in functions
Here's the code I already have:

    maximum = 0
    result = []
    max_key = None
    for i in scores:
        value = scores[i]
        if value > maximum:
            maximum = scores[i]
            max_key = i
    return max_key

CodePudding user response：

Hint: You need to loop over the scores twice: once to get the max value, and a second time to get all of the keys with that value.

CodePudding user response：

Here's a way:

scores = {'a':2,'b':1,'c':2}
high = None
for score in scores.values():
    if high is None or score > high:
        high = score
keys = [k for k, v in scores.items() if v == high]
print(keys)

First loop finds the maximum (without using the built-in max() function). Then, a list comprehension collects all keys in the input scores with value matching the maximum.

CodePudding user response：

Iterates through dict, replacing results if new max found, and adding index to results if same max found.

def fancy_max(scores):
    maximum = 0
    for i in scores:
        value = scores[i]
        if value > maximum:
            maximum = value
            result = [i]
        elif value == maximum:
            result.append(i)
    return result

s = {'a':2,'b':1,'q':5, 'c':2, 'd':4, 'j':5}
out = fancy_max(s)
print(out)

Output:

['q', 'j']