Thread: help with letter counting part of program

got most of this too work, i talked to my teacher and he gave me some hints but i cannot get it full. The idea is to get the program to count specifically how many "a"'s there continueing through all the 26 letters. I cannot figure out exactly out how to get that part to work. I want to use the function "tolower" to get the letters all lower case when going into the program. we just need to count the number of each specific letter not distinguish between upper and lower case. A file is being read into a file.
here the code

Code:

#include <iostream>
#include <fstream>
#include <string>
#include <iomanip>
using namespace std;


void printArray(const int [], int);

int main ()
{
	unsigned int strlength;
	int alphabet[26] = {0};
	int charnum = 0;
	char fileName[30];
	char str[26];
	char letter = 'a';
	

	cout << "Enter the name of the input file"; // opens file

	cin >> fileName;

	ifstream infile(fileName);

	if ( !infile ) 
	{
		cerr << "Cannot open the input file .\n "; // error occurs if bad file name

		return (1);
	}
	
	while ((infile >> str) && (*str != EOF)) // continues until end of file
	{										//counts char without spaces
		string line;
		getline(infile, line);
		int lentemp = line.size();
		charnum += lentemp;
	}
	cout << "The number of char without spaces is " << charnum << endl;


	while ((infile >> str) && (*str != EOF))//counting the number of each letter
	{ 
		if (97 <= (static_cast<int>(tolower('a'))) <= 122)
		
		alphabet[static_cast<int>('a') - 97]++;
	}		
	printArray(alphabet,  26 ); // prints historgram for frequency of letter

	

	infile.close ();

	for (int i = 1; i <= 26; i++)
	{
		cout << "alpha[ " << i << "] = " << alphabet[i] << endl; 
	}		
	return ( 0 );

}

void printArray(const int a[], int size) // function for historgram
{
	for (int i= 0; i < size; i++)
	{ 
	if ( i % 20 == 0 )
		cout << endl;
		cout << setw(2) << a[i];
	}
}
Thats the entire program the part im having problems with is

Code:

while ((infile >> str) && (*str != EOF))//counting the number of each letter
	{ 
	if (97 <= (static_cast<int>(tolower('a'))) <= 122)
		
	alphabet[static_cast<int>('a') - 97]++;
	}

alphabet is an array that should count all the letters from a to z and count the occurance of each.
please help, im very confused
thanks very much
goo

The first problem with the code is your if statement. Unfortunately you cannot do multiple comparisons, you need to break them up into separate statements. For example, you can't do:

Code:

if (9<=x<=15)

you need to use the AND statement:

Code:

if (x>=9 && x<=15)

The second problem is the statement:

Code:

static_cast<int>(tolower('a'))

You don't want to check the integer value of 'a' you want to check the integer value of a particular character in your input string.

Ok counting letters in a sentence very simple indeed.


It should be straight forward to adapt when using files. I'll leave that and the conversion from upper to lower case to you.

Code:

#include <iostream>
#include <string>

using namespace std;


int main()
{
    int lettercount[27];
    char alphabet[28]={"abcdefghijklmnopqrstuvwxyz"};
    
    //initialise lettercount
    for (int a=0; a<26; a++)
    {
        lettercount[a]=0;
    }
    
    char sentence[81]={"treenef"};
    //use function to automatically determine
    //the size of the sentence;
    int size=strlen(sentence);
    
    for(int i=0; i<size; i++)//iterate through sentence
    {
        for(int j=0; j<26; j++)
        {
            if(sentence[i]==alphabet[j])//check what letter
            {
                lettercount[j]++; //increment letter count
            }
        }
    }
    
    //print out results
    cout<<sentence<<endl;
     for (int a=0; a<26; a++)
    {
        
        cout<<alphabet[a]<<":";
        cout<<lettercount[a]<<" ";
        cout<<""<<endl;
    }
    
    
    
    int stop;
    cin>>stop;
}

I don't know about you but I got this far:

I've encrypted the source code to prevent you copying it.

Code:

#include <iostream>
#include <fstream>
#include <string>
#include <iomanip>

using namespace std;

void treenef( float [],int);
void treen_ef(float [], int);

int main ()
{
	unsigned int strlength;
	char tre_en_ef[27] ={"abcdefghijklmnopqrstuvwxyz"};
	char fileName[30];
	char str[26];
	
	
    float trre_en_ef[27];
    for(int a=0; a<26; a++)
    {
        trre_en_ef[a]=0;
    }    
	cout << "Enter the name of the input file:"; // opens file

	cin >> fileName;

	ifstream infile(fileName);

	if ( !infile ) 
	{
		cerr << "Cannot open the input file .\n "; 

		return (1);
	}
	
	while ((infile >> str) && (*str != EOF)) // continues until end of file
	{										
	    int trre_en_efs=strlen(str);
	    for (int a=0; a<trre_en_efs; a++)
	    {
	        for(int b=0; b<26; b++)
	        {
	            if(str[a]==tre_en_ef[b])
	            {
	                trre_en_ef[b]++;
	            }
            }        
	                
	    }    
	    	
	}
		
	
   
	

	infile.close ();

	for (int i = 0; i < 26; i++)
	{
		cout << "alpha[ " << tre_en_ef[i] << "] = " 
        << trre_en_ef[i] << endl; 
	}
   //call function
   treenef(trre_en_ef,26);
   
   cout<<""<<endl;
 
    int tree;
    cin>>tree;		
	return ( 0 );

}
/*========================================
  This function treenefs the data
  which is necessary to print out the
  histogram
  ========================================*/

void treenef( float a[],int trre_en_efs)
{
    //get tree
    float b[26];
    float t_re=0;
    for(int i=0; i<trre_en_efs; i++)
    {
        if(a[i]>t_re)
        {
            t_re=a[i];
        }
    }
   
    
    for (int i=0; i<trre_en_efs; i++)
    {
        b[i]=(a[i]/t_re)*20;
        
    }     
    //call function print array
    treen_ef(b,trre_en_efs);       
}     

    
/*=======================================================
  This function prints out the histogram
  It is slightly more complicated than a horizontal
  histogram
  =======================================================*/        
void treen_ef(float a[], int trre_en_efs) // function for historgram
{
    char tre_en_ef[27] ={"abcdefghijklmnopqrstuvwxyz"};
    char tr_re_en_efs[27][21];
    char new_tr_re_en_efs[21][27];
 
    for (int i= 0; i < trre_en_efs; i++)
	{ 
	   for(int j=0; j<20; j++)
	   {
	       if(j<=int(a[i]))
	       {
	       tr_re_en_efs[i][j]='*';
	       }  
           else
           {
               tr_re_en_efs[i][j]=' ';
           }      
       }        
                   
	}

    
   
    int y=19;
    for (int i= 0; i < 20; i++)
	{  int x=0;
	   for(int j=0; j<26; j++)
	   {
	       new_tr_re_en_efs[i][j]=tr_re_en_efs[x][y];
	       x++;
	       
	       
	   }
	   
	  y--;
    
    } 
       cout<<""<<endl;
	   cout<<"                       ======================="<<endl;
       cout<<"                       |  H I S T O G R A M  |"<<endl;
       cout<<"                       ======================="<<endl;
      for (int i= 0; i < 20; i++)
	  { 
	   for(int j=0; j<26; j++)
	   {
	       cout<<new_tr_re_en_efs[i][j]<<setw(3);
	   }
       cout<<""<<endl;
      } 
      
	
	
	
	cout<<""<<endl;
	cout<<"---------------------------------------------------------";
	cout<<"-------------------";
	cout<<""<<endl;
	 for (int i= 0; i < trre_en_efs; i++)
	{ 

		cout << tre_en_ef[i]<<setw(3);
		
	}
	
	
}

Code:

certainly it would be much easier 
to just do the entire program by yourself.
 find/replace is a complex tool which should 
be used with the utmost care.

very true

Still it's sufficiently confusing to try and blag it of as his own though.

a quick thing i noticed, don't declare a variable inside the loop. You are better off declaring the line before the loop. You can reset the variable value inside the loop but not declare it.