Word Length Frequency

// word_len_histo.cpp : reads words and lists distribution
//                      of word lengths.
// Fred Swartz, 2002-09-01

// This would be nice to turn into an OO program, where
// a class represented a distribution of values.
// Some elements which are globals here would turn into
// private member elements in the class (eg, valueCount).


//--- includes
#include 
#include 
#include 
using namespace std;

//--- prototypes
void  countValue(int cnt);
float getAverage();

//--- constants
const int BINS = 21;  // how many numbers can be counted

//--- globals
int valueCount[BINS]; // bins used for counting each number
int totalChars = 0;   // total number of characters

//=========================================================== main
int main() {

    char c;              // input character
    int  wordLen = 0;    // 0 if not in word, else word length

    //--- Initialize counts to zero
    for (int i=0; i
        valueCount[i] = 0;
    }

    //--- Read chars in loop and decide if in a word or not.
    while (cin.get(c)) {
        if (isalpha(c)) { // letters are in words, so
            wordLen++;    // add one to the word length
        } else {
            countValue(wordLen); // end of word
            wordLen = 0;  // not in a word, set to zero
        }
    }
    countValue(wordLen);  // necessary if word ended in EOF

    //--- print the number of words of each length
    cout << "Why does this line disappear?" << endl;
    cout << "Word length    Frequency" << endl;
    for (int j=1; j
        cout << setw(6) << right << j << "       " 
             << setw(8) << right << valueCount[j] << endl;
    }

    //--- print average length
    cout << "\nAverage word length: " << getAverage() << endl;

    return 0;
}//end main


//==================================================== countValue
void countValue(int cnt) {
    if (cnt > 0) {
        // this must be the end of a word
        if (cnt > 20) {
            cnt = 20;  // longer than 20 counts as 20
        }
        valueCount[cnt]++; // count in correct bin
    }
    totalChars += cnt;
}//end countWord


//==================================================== getAverage
float getAverage() {
    int totalCount  = 0;

    for (int i=0; i
        totalCount  += valueCount[i];
    }
    if (totalCount > 0) {
        return (float)totalChars/totalCount;
    } else {
        return 0.0;
    }
}//end getAverage

Reading from file or Reading integers from file

#include <iostream>
#include <iomanip>
#include <fstream>
#include <cstdlib>

using namespace std;

int main() {
    int sum = 0;
    int x;
    ifstream inFile;

    inFile.open("integers.txt"); // read integers from text file
    if (!inFile) {
        cout << "Unable to open file";
        exit(0); // terminate with error
    }


while (inFile >> x) {
        sum = sum+x;
    }
    inFile.close();

cout << "Sum = " << sum << endl;
    return 0;
}