Baby names popularity program - c++

Question

I have to write a program that allows the user to input a name from the keyboard. The program should then read from the file and search for matching name among the girls and boys. If a match is found it should output the rank of the name. The program should also indicate if there is no match.
Here is my program :
ifstream fin;
fin.open( "/Users/fashiontekk/Downloads/Assignment 3 Instructions/babyNames2017.dat" );
string nameInput;
string boyName;
string girlName;
int rank= 0;
int boyRank= 0;
int girlRank =0;
cout << " Which name would you like to check? < no space in names please > " << endl;
cin >> nameInput;
fin >> boyName;
fin >> girlName;
rank++;
cout << " After going through an extensive search here is what we found out - " << endl;
if (nameInput == boyName) {
cout << nameInput << " is ranked " << rank << " in popularity among boys. " << endl;
boyRank = rank;
}
if (nameInput == girlName) {
cout << nameInput << " is ranked " << rank << " in popularity among girls. " << endl;
girlRank = rank;
}
if (boyRank < 1 || boyRank > 1000) {
cout << nameInput << " is not ranked among the top 1000 boys name. " << endl;
}
if (girlRank < 1 || girlRank > 1000) {
cout << nameInput << " is not ranked among the top 1000 girls name. " << endl;
}
cout << " Hope that is the result you were looking for ... Ending program. " << endl;
fin.close();
return 0;
}
However, my output window says : Which name would you like to check? < no space in names please >
Program ended with exit code: 0Liam
After going through an extensive search here is what we found out -
Liam is ranked 1 in popularity among girls.
Liam is not ranked among the top 1000 boys name.
Hope that is the result you were looking for ... Ending program.
I tried to type in Liam which the most popular boys name according to the file provided. I feel like my coding is right however I can't spot the error.

Answer 1

It is my first year in Computer Science and I don't can't find my mistake.
OK, we've all been there at some point. You need to work on your debugging skills — you're gonna need them. In particular, spend some time learning to use gdb or whatever debugger you have available. A good debugger will let you step through a program a line at a time, watch variables, and generally checkout every possible thing that could be a problem.
So let's take a look at your code with an eye toward debugging it. It's handy that the message that's emitted comes right up near the top of the program — that really narrows down the places where you could be going wrong. Here's the first part of your program:
ifstream fin;
fin.open( "babyNames2017.dat" );
if (!fin) {
cout << " File not processed ";
return 0;
}
So, the first line just declares the variable for your input file. There's not much that can go wrong there. The next line opens the file... hmmm... I'm not sure if that might be a problem or not, so let's stick a pin in it for now and keep going. The next line, if (!fin) {, is a condition that only succeeds if !fin is true, which means that fin must evaluate to false to enter this block. And it clearly does enter this block, because that's the part of the code that emits the "File not processed" message. So fin must be 0, right? OK, so how can fin possibly be 0?
I don't have the C++ iostreams documentation handy, but you should go look up what that fin.open(...) call does if it fails. Given the way you've written the code, it looks very much like you'd expect failure to set fin to 0, right? So how can that call fail? Well, for starters, you're only supplying the file name... the working directory when you run the program might be set to something you don't expect, so the file isn't found. Or the file name might not match the name of the actual file. Remember that some file systems are case sensitive, and if you're working with such a file system then the open call will fail if the file is just named babynames2017.dat or BabyNames2017.dat or anything else that doesn't exactly match your file.