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Breaking a single string into multiple strings C++?

I need to input 3 full names separated by commas

Full Name 1: John, Smith, Flynn

Full Name 2: Walter, Kennedy, Roberts

Full Name 3: Sam, Bass, Clinton

Then output it like this

First Name 1: John

First Name 2: Walter

First Name 3: Sam

Middle Name 1: Smith

Middle Name 2: Kennedy

Middle Name 3: Bass

Last Name 1: Flynn

Last Name 2: Roberts

Last Name 3: Clinton

How do i do these? so far this is my code

#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;

int main () {
    char first[3][100];
    char middle[3][100];
 开发者_JAVA技巧   char last[3][100];
    char full[3][100];
    int i; 

    cout << "Enter 3 Full Names <first, middle and last names separated by comma>:" << endl;
    for (i=0; i<3; i++) {
         cout << "Full Name " << i+1 << ":" ;
        gets (full[i]);          
    }

    cout << "The first names are: " << endl;
    for (i=0; i<3; i++) {
        strcpy (first[i], full[i]);
        if (strcmp (first[i], ", ")) {
            cout << "First Name "<< i+1 << ":" ;
            strcpy ( first[i], full[i] );
            cout << (first[i]);
            cout << endl;   
        }
    } 
    cout << "The middle names are: " << endl;
    for (i=0; i<3; i++) {
        cout << "Middle Name "<< i+1 << ":" ;
        cout << (middle[i]);
        cout << endl;
    }
    cout << "The last names are: " << endl;
    for (i=0; i<3; i++) {
        cout << "Last Name "<< i+1 << ":" ;
        cout << (last[i]);
        cout << endl;
    }
    system("pause");
    return 0;
}


I think here what you want to is a split method for string class, the method should like this:

void SplitName(const string& fullName, const string& delims, vector<string>& names)
{
    size_t i = 0;
    size_t j = 0;
    while (i < fullName.size())
    {
        i = fullName.find_first_not_of(delims, i);
        j = fullName.find_first_of(delims, i);
        if (i < fullName.size())
        {
            names.push_back(fullName.substr(i, j - i));
        }
        i = j;
    }
}

you can define the ":," as delims, then names[1] is First Name, names[2] is Middle Name, names[3] is Last Name.


I'd probably do something like this:

Edit: after some thought, I've decided the duplication really did bother me too much, so I've eliminated it. I'm not sure it's technically allowed (std::string isn't a POD) but it seems to work, and strikes me as nicer and more scalable.

#include <iostream>
#include <sstream>
#include <algorithm>
#include <string>
#include <vector>
#include <iterator>

struct name { 
    std::string first, middle, last;
};

std::istream &operator>>(std::istream &is, name &n) { 
    char ch;
    is.ignore((unsigned)-1, ':');
    is.ignore(1);

    std::getline(is, n.first, ',');
    std::getline(is, n.middle, ',');
    std::getline(is, n.last);
    return is;
}

struct item { 
    size_t offset;
    char *caption;
};

void show(name const &n, item const &i) { 
    // as predicted, eliminating the duplication did lead to one gnarly line of code:
    std::string &name = *(std::string *)((char *)&n+i.offset);
    std::cout << i.caption << name << "\n";
}

int main() {     
    std::vector<name> names;

    std::string raw_data("Full Name 1: John, Smith, Flynn\nFull Name 2: Walter, Kennedy, Roberts\nFull Name 3: Sam, Bass, Clinton");

    std::istringstream infile(raw_data);

    std::copy(std::istream_iterator<name>(infile),
              std::istream_iterator<name>(),
              std::back_inserter(names));

    item items[] = { 
        {offsetof(name, first), "First Name: "},
        {offsetof(name, middle), "Middle Name: "},
        {offsetof(name, last), "Last name: "} 
    };

    for (int i=0; i<3; i++) {
        for (int j=0; j<3; j++)
            show(names[j], items[i]);
        std::cout << "\n";
    }
    return 0;
}


void DumpName(char*  pBuffer, char cDelimiter, int iCounter);

int _tmain(int argc, _TCHAR* argv[])
{
    char full[3][100];

    cout << "Enter 3 Full Names <first, middle and last names separated by comma>:" << endl;
    for (int i=0; i<3; i++) {
         cout << "Full Name " << i+1 << ":" ;
        gets (full[i]);          
    }

    for(int i=0; i<3; i++)
    {
        cout << "First Name "<< i+1 << ":" ;
        DumpName(full[i], ',', 0);
    }

    for(int i=0; i<3; i++)
    {
        cout << "Middle Name "<< i+1 << ":" ;
        DumpName(full[i], ',', 1);
    }

    for(int i=0; i<3; i++)
    {
        cout << "Last Name "<< i+1 << ":" ;
        DumpName(full[i], ',', 2);
    }

    return 0;
}

void DumpName(char*  pBuffer, char cDelimiter, int iCounter)
{
    int iFound = 0;

    char* pStart = pBuffer;
    char* pCurrent = pBuffer;
    while(*pCurrent != '\0')
    {
        if(*pCurrent == cDelimiter)
        {
            if(iFound == iCounter)
            {
                *pCurrent = '\0';
                cout << pStart << endl;
                *pCurrent = cDelimiter;
                return;
            }

            pStart = pCurrent;
            pStart ++;
            iFound ++;
        }

        pCurrent ++;
    }

    if((iCounter - iFound) == 0)
        cout << pStart << endl;
}
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