Mainly technical problems:
One difference from your code is the the vector part which I thought is a structure containing course_abbreviation, credit and grade. Yours is a vector of string. Which is the part I did not catch with your code?
code:
Highlighted LINE 54, 65 & 66 are the parts throwing out lots of errors. Thanks!
That wasn't what I meant by using pairs, but I think you'd do map.insert( std::pair<type,type>(valuea, valueb) )
The reason your 'atoi' didn't work is because you're trying to call c_str on something that's already a c string! atoi(sptr); stoi is just an alias to atoi on systems that have it(unlike mine, which did not.) Use atoi.
That 'courses' structure doesn't look useful for anything, not sure why you have it, all the information is in 'marks'.
Finally -- I think you missed the point. Imagine how they make these map<>'s, it's going to be a list or array of some kind internally, right? So in memory somewhere there is a structure like this:
This isn't just wasted memory, it creates the opportunity for your program to store "impossible" states where element.key.studentid and element.value.studentid disagree. This seems even more likely to happen when keeping the same value around in different places as different types!
So:
Use studentid as an integer everywhere.
Never duplicate your key inside your data, only use it to fetch your data.
Thanks! Courses is a vector of struct, which seems needed as (map) value of marks. It is to hold the grades structures when more courses are pushed into the vector until eof. So the vector sizes are very likely different for each student. In the example input file, there are 3 students that have 3, 4 and 5 courses, respectively.
like:
Did I miss anything?
Your program is a mess, had no error checking and crashed nonstop. That's why strtok is considered "evil" -- if you don't bother checking, bad things will happen. But a little checking makes it fine.
Nearly every line ended up commented out and replaced, I had to rewrite it instead.
Courses is a vector of struct, which seems needed as (map) value of marks. It is to hold the grades structures when more courses are pushed into the vector until eof.
Why? A vector can hold as many as you want already, and if you want to know how large it is, just ask: (something).size()
Logically I was thinking in a totally different way! Definitely I missed many points that may be critical for programming. Let me try out your code first. Thanks a lot!
In AWK
For 3 individual vectors of the form:
-2.772 -9.341 -2.857
-5.140 -6.597 -1.823
-2.730 -5.615 1.159
I would like to write a script that parses line by line to (i) normalise, (ii) divide by the norm for *each* vector.
I.e.
sqrt(-2.772^2 + -9.341^2 + -2.857^2)=10.154
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struct test
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int a;
int b;
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struct TData
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struct one
{
struct two;
}
struct two
{
three;
}
one->two->three
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Hi
i have the following structure
struct S
{
char Mod_num;
char val;
char chr_nm_cd;
}
I am reading a 2GB file and inserting into the structure and writing into a vector.
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