C++ Read in Name and Numbers From File

Howdy. I'thousand completely new to programming and I have a question about a program I have to write.

I need to read some numbers from a file and display the sum of the numbers > 0, count of the numbers > 0, sum of the number < 0, count of the numbers < 0, and a count of the numbers == 0.

I'm completely stuck on how I should write the while loops. Hell, how I should write anything. I think I may have the beginning correct. This is my measly attempt:

1 2 3 4 v half-dozen seven 8 ix x 11 12 13 fourteen fifteen 16 17 18 xix 20 21 22 23 24 25 26 27 28

#include <iostream> #include <fstream> using namespace std; int main() { ifstream inFile; int value1, value2, value3, value4; int sum; int count = 0; inFile.open("My_Path"); inFile >> value1, value2, value3, value4; inFile.close(); sum = value1 + value2 + value3 + value4; while ( sum > 0 ) { cout << "Sum of #'south > 0 : "; sum += value; count++; } return 0; }

inFile >> value1, value2, value3, value4;

should be

inFile >> value1 >> value2 >> value3 >> value4;

assuming that each of the values are separated past a whitespace.

Yep, didn't catch that typo. My master defoliation lies with how would I get the counts and sums.

Should I be using a for loop or a while loop? Can someone at least point me in that management? I'm currently have

for (int value = 0; value > 0; count++)

Is that wrong?

Last edited on

I thought I was on the right rail for this, merely the output displayed an endless amount of sixes.

1 2 3 4 5 6 seven 8 9 10 11 12 thirteen 14 15 16 17 eighteen 19 20 21 22 23 24 25 26 27

#include <iostream> #include <fstream> using namespace std; int master() { ifstream inFile; int value; inFile.open up("My_Path.txt"); if (!inFile) { cout << "\nError opening file.\n"; return thirteen; } while (inFile >> value) { while (value > 0) { cout << value; } } inFile.shut(); return 0; }

Last edited on

@Guy1988

For line 19, try if (value > 0)

I'm thinking that te beginning number read in with the infile, was a 6. So, since value never decreases and become less than 0, you lot enter an endless loop, e'er displaying the outset number, which was a 6;

Yep, that'due south what I concluded upward doing. Would I nest the other if statements inside? To add the counts for each if statement, practise I add count++ inside each one?

If it helps, the numbers in my file are -nine, half dozen, 0, and 4.

@Guy1988

You seem to be referring to your original postal service code, as there is no count, or other if statement, in it. Seems the above program was simply a examination to get things figured out..

1 2 3 4 5 6 7 8 9 ten 11 12 13 14 xv 16 17 18 19 20 21 22 23 24 25

#include <iostream> #include <fstream> using namespace std; int main() { ifstream inFile; int value; int sum = 0; // Initialize to 0; int count = 0;// aforementioned as above inFile.open up("My_Path.txt"); while(inFile >> value) // While file can exist read in ( You lot can increase numbers in text { count++; // Increase count cout << "Sum of #'s > " << count; // Print out variable sum += value; // Increase sum total } inFile.shut(); // Close file. cout << "Sum total of all " << count << " numbers, was "<< sum << endl; // Print out the results return 0; }

If information technology helps, the numbers in my file are -9, 6, 0, and 4.

Aye. Get-go number that was greater than 0 is the half dozen. Line 19 disregarded the -9, since it was non greater than 0

My first post was me completely lost with what to practise. I then idea I had to nest while loops.

1 2 3 iv 5 6

while(inFile >> value) // While file can exist read in ( You can increase numbers in text { count++; // Increase count cout << "Sum of #'s > " << count; // Print out variable sum += value; // Increment sum full }

This is what I'm stuck on. How practice I get the multiple values read and display each count and sum for >, <, and then brandish the count for == 0.

This is what I accept now:

1 ii 3 4 5 6 7 8 9 ten 11 12 13 14 15 16

inFile >> value; while (inFile) { if (value > 0) { count++; } else if (value < 0) { count++; } else { count++; } }

How do I display separate counts and sums for each of the branched if statements?

You lot need to have 3 sum variables and 3 count variables and test as each new number is read in:

1. setup variables count_of_negative_numbers, sum_of_ngative numbers, count_of_positive_numbers etc etc
2. read a new number chosen new_number
3. if new_number < 0
and then increase count-of_negative_numbers and add together new_number to sum_of_negative numbers

4. if new_number == 0 ... aforementioned procedure
5. do the aforementioned for new_number > 0 ...
...

half-dozen. loop back to get a new new_number

Terminal edited on

This is so frustrating for me, I'm not understanding.

What practice I read a new number for? Everything that needs to be read is in the file. What I have to do is brandish the sums and counts for those numbers.

I've got something that looks like this at present.

i 2 3 4 5 half dozen seven viii 9 10 11 12 13 14 fifteen sixteen 17 18 19 xx 21 22 23 24 25 26 27 28 29 thirty 31 32 33 34 35 36

#include <iostream> #include <fstream> using namespace std; int main() { ifstream inFile; int countn = 0, countp = 0, countz = 0; int value; int sumn, sump, sumz, sum; inFile.open up("My_Path.txt"); inFile >> value; while (inFile) { if (value > 0) { sum += sump; countp++; } else if (value < 0) { countn++; } else { countz++; } } inFile.close(); cout << "Sum of #'s > 0: " << countp; render 0; }

Now, when I execute, cypher is displayed.

What is the contents of the file "My_Path.txt"?

The numbers I listed: -nine, 6, 0, and 4 in Notepad.

I made sure the file opened first, before I did anything else, and it processed.

I'thou getting no output displayed when executing. What's going on?

ane 2 3 four 5 6 seven 8 ix 10 eleven 12 13 14 15 xvi 17 18 19 20 21 22 23 24 25 26 27 28 29 thirty 31 32 33 34 35 36 37 38 39 xl 41 42 43 44 45 46 47 48

#include <iostream> #include <fstream> using namespace std; int main() { ifstream inFile; int countn, countp, countz; int value; int sump, sumn, sumz; inFile.open("My_Path.txt"); if (!inFile) { cout << "error"; return xiii; } inFile >> value; while (inFile) { if (value > 0) { countp++; sump += value; } else if (value < 0) { countn++; sumn += value; } else { countz++; sumz += value; } } inFile.close(); cout << "Sum of #'due south > 0: " << sump; cout << "Count of the #'s > 0: " << countp; cout << "Sum of the #'s < 0: " << sumn; cout << "Count of the #'southward < 0: " << countn; cout << "Count of the #'s = 0: " << countz; return 0; }

Concluding edited on

one 2 three 4 five

else { countz++; sumz += value; } }

Should be :

1 2 3 4 5

else { countz++; sumz += value; } inFile >> value; }

In that location is an infinite loop. The program never finishes. It gets stuck in the while loop at line 21.

I was getting help from someone and now I'm getting crazy large numbers in my output.

So is my whole structure incorrect?

badgerditer1940.blogspot.com

Source: https://www.cplusplus.com/forum/general/198475/

Share this post