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Start your free trialMoira Lawrie-Martyn
8,073 PointsBest way to handle an array and nested loops
Hey guys,
I'm struggling with an array and nested loops and wanted to bounce it off the community.
What I need to do is take an array of >50000 values and loop through it.
The first thing I need to do is capture the year of the value and group together all the values that have the same year
The second thing I need to do is for each year, group those into months
The third thing I need to do is average out the values in each month (easy part)
I was thinking something similar to:
year = array[0].year;
for(int i = 0; i < array.length; i++)
{
if(year == array[i].year)
{
month = array[i].month;
while(month = array[i].month)
{
average the values and collect into another array
}
month = array[i].month
}
else
{
year = array[i].year
}
}
But I dunno...the logic in my brain tells me this isn't gonna work and values are going to get skipped. I can't say "I'll just collect them into separate arrays" because that isn't extensible.
I can't hard code anything because I don't know what data is going to run through it once it's built but I'm seriously stuck here.
Can anyone give me some guidance here?
Thanks! <3
1 Answer
Steven Parker
231,184 PointsI assume you meant to have a comparison (==) instead of an assignment (=) in the "while" loop; but even so, unless one of the terms gets changed in the loop body that loop will never end.
But you shouldn't need a nested loop if you have a place (another array or a list) to accumulate sums and counts of each month/year. Then after the main loop finishes, a much shorter one could compute the averages, and output them (if desired).
Another thing you might consider as an alternative to a loop is a Linq query where you group by the month.