In this piece of code, I'm attempting to calculate the average of the person's scores as entered by the user. Code :

if __name__ == '__main__':
    n = int(input())
    student_marks = {}
    for _ in range(n):
        name, *line = input().split()
        scores = list(map(float, line))
        student_marks[name] = scores
    query_name = input()

for i in name:
    if(query_name == i):
        sos = float(sum(scores))
        lengs = int(len(scores))
        avg = float(sos/lengs)

print('.2f'%avg)

Error shown in the compiler :

Traceback (most recent call last): File "/tmp/submission/20220330/18/46/hackerrank-9395c8cfa7010e9d6e7964a4ac3c813/code/Solution.py", line 16, in module
print('.2f'%avg)
NameError: name 'avg' is not defined

CodePudding user response：

There's no need for a second loop at all. You have a dictionary indexed by name, so look up the scores you want to get by using query_name as a key:

student_marks = {}
for _ in range(int(input())):
    name, *line = input().split()
    scores = list(map(float, line))
    student_marks[name] = scores

query_name = input()
scores = student_marks[query_name]
print(f"{sum(scores)/len(scores):.2f}")

The loop for i in name was just iterating over the letters of name, which will just be whatever the last name you entered was; not at all useful for what you're trying to do.

Note that you also don't need any of the following:

• if __name__ == '__main__' - this is only useful if you're working with multiple files, and the way you were using it, half of the code was outside the if block anyway.
• int(len(...)) -- len already returns an int, no need to convert it
• float(sum(...)) -- sum of a list of floats is already going to be a float