Read numeric and change to alpha

[calz]

I need a program that checks for numeric in a sentence and change it to alpha given by user. If it find alphanumeric it must skip

[mutexe]

show what you've got so far.

[calz]

#include <iostream>
#include <string>
#include <cctype>

int main()
{
using namespace std;

string one_line, sentence="";
cout <<"Enter a sentence."<<endl;
do
{
getline(cin, one_line);
if (sentence.length()==0)
sentence=one_line;
else
sentence=sentence +" "+ one_line;
}while (one_line.find(".")==string::npos);
cout <<"Your sentence corrected for capitalization is"<<endl;
cout <<sentence <<endl;
char current;
bool found_whitespace=false;
for (int i=0; i <sentence.length();i++)
{
current=sentence[i];
if (i==0)
current=toupper(current);
else
current=tolower(current);
if(isspace(current))
{
if (found_whitespace==false)
{
cout << current;
found_whitespace=true;
}
else
{
//do nothing because we have repeat whitespace
}
}
else //not whitespace
{
cout <<current;
found_whitespace=false;
}
}
cout <<endl;
return 0;
}

[mutexe]

how has this code got anything to do with what you want to write?

[calz]

This program should also look for numeric and change it to "X"

#include <iostream>
#include <string>
#include <cctype>

int main()
{
using namespace std;

string one_line, sentence="";
cout <<"Enter a sentence."<<endl;
do
{
getline(cin, one_line);
if (sentence.length()==0)
sentence=one_line;
else
sentence=sentence +" "+ one_line;
}while (one_line.find(".")==string::npos);
cout <<"Your sentence corrected for capitalization is"<<endl;
cout <<sentence <<endl;
char current;
bool found_whitespace=false;
for (int i=0; i <sentence.length();i++)
{
current=sentence[i];
if (i==0)
current=toupper(current);
else
current=tolower(current);
if(isspace(current))
{
if (found_whitespace==false)
{
cout << current;
found_whitespace=true;
}
else
{
//do nothing because we have repeat whitespace
}
}
else //not whitespace
{
cout <<current;
found_whitespace=false;
}
}
cout <<endl;
return 0;
}

[CodeWriter]

Where did you find the above code?

It doesn't seem to look for numeric characters.

You enter a sentence which you must end with a period (full stop) "."

It makes the first character an upper case and converts all other character to lower case.

It checks for a " " character for some reason...

I assume you want to modify it to do something else?

So the code is an example of how to input a sentence and gives an example of how a sentence can be processed.
You need to insert code to process it the way you want.

Here is a simple example in which the process is to convert any lower case characters to upper case.

#include <iostream>
#include <string>
//#include <cctype>
using namespace std;

int main()
{
    string one_line, sentence="";
    cout <<"Enter a sentence and end it with a full stop"<<endl;

    // get a sentence ending with a period (full stop).
    do
    {
        getline(cin, one_line);
        if (sentence.length()==0)
            sentence=one_line;
        else
            sentence=sentence +" "+ one_line;
    }while (one_line.find(".") == string::npos);


    // convert any lowercase characters to uppercase characters
    char current;
    for (int i=0; i <sentence.length();i++)
    {
        sentence[i]= toupper(sentence[i]);
    }

    cout << sentence;   // print the result
    cout <<endl;
    return 0;
}

[calz]

yesy I understand, but in the same program/sentence should the user enter numeric value then it must replace the numeric to an "X"

[CodeWriter]

Just say in words what you want and convert it to C++ code using your knowledge of C++ and library functions like isDigit().

for each letter in the sentence,
if letter is a digit then
make it an "x"

[calz]

Yes but it should not change eg alphanumeric. Peter88 should remain Peter88 and not PeterXX

[CodeWriter]

Then you need to extract the words from the sentence and determine if they start with something other than a digit. One way might be to look for a space character after which you can check if the next character is a digit or not. Is that what the sample code you gave does?
Your first post did not make it clear that you were talking about more than just a character type.
Figure out how you would do it with pen and paper and convert those steps into C++ code.
Remember a string is just a list of characters and the variable i in the above examples points to the position in that list.

And what about 88Peter?