plz help me with simple string comparison.

This is a discussion on plz help me with simple string comparison. within the C++ Programming forums, part of the General Programming Boards category; i have no idea why this isn't working.. plz plz help a guy out. Code: char monthNames[2][10] = {"jan", "feb"}; ...

  1. #1
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    plz help me with simple string comparison.

    i have no idea why this isn't working.. plz plz help a guy out.


    Code:
        char monthNames[2][10] = {"jan", "feb"};
        char monthSelection[10];
    // printf(monthNames[0]);
        int check = 0;
        while(check != 1)
        {
            printf("Enter the month: (e.g. January ) ");
            gets(monthSelection);
            printf(monthSelection);
            printf(monthNames[0]);
    //        for (int i = 0; i < 2; i++)
    //        {
                if (monthSelection == monthNames[0])
                {
                    printf("correct");
                    check = 1;
                    break;
                }
    //        }
        }
    in the end i want the program to check to see if the input exists in the array. i was thinking of using a for loop to check every element of the array.. but i can't even get this script to work..

  2. #2
    C++まいる!Cをこわせ! Elysia's Avatar
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    You should be using std::string to avoid these pitfalls.
    Code:
    std::string monthNames[2] = { "Jan", "Feb" };
    But wait... isn't this pure C code? Do you want C instead of C++?
    And don't use gets; use fgets (in case you are using C).
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.

  3. #3
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    this is a homework assignment.. the only header thats included is
    #include <stdio.h>

    does that support std::string?

    also is there a faster method of getting the same result?
    or better method.

  4. #4
    C++まいる!Cをこわせ! Elysia's Avatar
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    Do you use C or C++?
    This is the C++ forum but your code is C.
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.

  5. #5
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    well i guess it's c. It's a c++ class tho but they gave a c example to work with.. sorry i will post on the c board.

  6. #6
    C++まいる!Cをこわせ! Elysia's Avatar
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    Well, if you can use C++, you might as well learn it, if you're willing.
    std::cout instead of printf, std::cin or std::getline instead of gets and std::string instead of char.
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.

  7. #7
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    cool. but why isn't the comparison working lol

  8. #8
    C++まいる!Cをこわせ! Elysia's Avatar
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    It will, if all strings are std::string. Comparing char* to char* won't work.
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.

  9. #9
    Dr Dipshi++ mike_g's Avatar
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    MegaManZZ: To compare stings include <cstring> and use strcmp. If it returns 0 your strings are the same, something like:
    Code:
    if( strcmp(string1, string2) == 0)
        // Match found

  10. #10
    C++まいる!Cをこわせ! Elysia's Avatar
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    For char* and char* and C, yeah, but not necessary for C++, so the question is what approach you're willing to take?
    C way:
    Code:
    const char* mystr1 = "My first string";
    const char* mystr2 = "My second string";
    if (strcmp(mystr1, mystr2) == 0)
    	; // Match
    C++ way:
    Code:
    std::string mystr1 = "My first string";
    std::string mystr2 = "My second string";
    if (mystr1 == mystr2)
    	; // Match
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.

  11. #11
    Dr Dipshi++ mike_g's Avatar
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    Its perfectly valid to use C style strings in C++. While there may be lots of benefits to using std::string somehow I doubt the OP cares.

  12. #12
    C++まいる!Cをこわせ! Elysia's Avatar
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    So it is, but when learning C++, you should try to do it the "C++" way and no the "C+" way, yes?
    So unless the extra benefits of C-style strings are required, it's better to use the C++ way...
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.

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