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Find a letter in a given word

Jhub (56)
Hello everyone,
I need to Write a program that takes a single word string from the user. After acquiring this input from the user, the program will use a loop to output whether the string contains either an ‘x’ or an ‘e’ (or both). I need to utilize only the size() and at() member functions of the string class as I iterate through the entire string and acquire each character individually to check its value.

What loop function would be best to use?
Also how would I use size and at functions here?

thank you all and here is where I am at.

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cout<<"enter a word"<<endl;
            cin>>word;
            std::string str (word);
                for (unsigned i=0; i<str.length(); ++i)
               
                    if((str.at(i)=='e') && (str.at(i)!='x'))
                    {
                        cout<<"Your word, "<<word<<", contains the character 'e'"<<endl;
                        
                    }
                    else if((str.at(i)=='x') && (str.at(i)!='e'))
                    {
                        cout<<"Your word, "<<word<<", contains the character 'x'"<<endl;
                    }
                    else if ((str.at(i)=='e') && (str.at(i)=='x'))
                    {
                        cout<<"Your word, "<<word<<", contains the character 'e'"<<endl;
                        cout<<"Your word, "<<word<<", contains the character 'x'"<<endl;
                    }
                    else
                    {
                        
                    }


this works except it repeats the cout if multiple x's or e's are found.
Last edited on
MiiNiPaa (8886)
What loop function would be best to use?
for loop
Also how would I use size and at functions here?
loop from 0 to size(). Use .at() istead of [] to access individual values.
Jhub (56)
This is where I am at :(


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  #include <iostream>
#include <string>

using namespace std;

int main ()

{
    int ex;
    int letter;
    int count;
    string word;
    cout<<"Which excercise? ";
    cin>>ex;
    cout<<endl;
    
    if(ex==1)
    {
        cout<<"Enter a word. "<<endl;
        cin>>word;
       
       int letter =1;
       while (letter<=word.size())
        {
           //if (word.find(letter)!='e')
            letter++;
        }
        cout<<"your word contains an 'e'"<<endl;
    }

Jhub (56)
thank you for your help I am working on the above code and will post it when I finish,

Thank you again!
Last edited on
Jhub (56)
ok this works if 'e' comes before 'x' in the word entered but if 'x' comes first it only finds 'x', how can I fix this?




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        cout<<"enter a word"<<endl;
            cin>>word;
            std::string str (word);
                for (unsigned i=0; i<str.length(); ++i)
               
                    if(str.at(i)=='e')
                    {
                        cout<<"Your word, "<<word<<", contains the character 'e'"<<endl;
                        
                    }
                    else if(str.at(i)=='x')
                    {
                        cout<<"we found x"<<endl;
                        break;
                    }
                    else
                    {
                        
                    }
MiiNiPaa (8886)
If you find x, you break the loop: line 14.
Jhub (56)
I solved the above problem but now if multiple 'e's or 'x's are enter it repeats my output statement that many times, how can I fix this?
I tried to use break but that breaks the next if statement as well.

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cout<<"enter a word"<<endl;
            cin>>word;
            std::string str (word);
                for (unsigned i=0; i<str.length(); ++i)
               
                    if((str.at(i)=='e') && (str.at(i)!='x'))
                    {
                        cout<<"Your word, "<<word<<", contains the character 'e'"<<endl;
                        
                    }
                    else if((str.at(i)=='x') && (str.at(i)!='e'))
                    {
                        cout<<"Your word, "<<word<<", contains the character 'x'"<<endl;
                    }
                    else if ((str.at(i)=='e') && (str.at(i)=='x'))
                    {
                        cout<<"Your word, "<<word<<", contains the character 'e'"<<endl;
                        cout<<"Your word, "<<word<<", contains the character 'x'"<<endl;
                    }
                    else
                    {
                        
                    }
MiiNiPaa (8886)
1) you do not need two conditions here as onecharacter cannot be both e and x.
2) create a boolean varialbles called efound and xfound.
Use them:
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//Variant 1
bool efound = false;
bool xfound = false;
for( int i = 0; i < str.size(); ++i) {
    if(str.at(i)=='e')
        efound = true;
    else if ((str.at(i)=='x')
        xfound = true;
}
if(efound)
    std::cout << cout<<"Your word, "<<word<<", contains the character 'e'"<<endl;
if(xfound)
    std::cout << cout<<"Your word, "<<word<<", contains the character 'x"<<endl;

//Variant 2
bool efound = false;
bool xfound = false;
for( int i = 0; i < str.size(); ++i) {
    if(str.at(i)=='e' && !efound) {
        efound = true;
        std::cout << cout<<"Your word, "<<word<<", contains the character 'e'"<<endl;
    } else if ((str.at(i)=='x' && !xfound) {
        xfound = true;
        std::cout << cout<<"Your word, "<<word<<", contains the character 'x"<<endl;
    } else if (xfound && efound) //if found both, no need to loop further
        break;
}
}
Jhub (56)
thank you so much miinipaa, I am still trying to take all what you typed in.
Jhub (56)
if I am reading this correctly variant 1 and 2 are two different ways to do it.
variant 1 seems much more simple
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