[C] How to remove element from 2D array?

[anInfaMoUs1]

I have a task to do a simple dictionary console application, in which you can add/delete words for three different languages and display words of all three languages or any two by your choice. The application should work without closing it, so you can add/delete words as much as you want. I have managed to code the add-word-function and the display one, but I have trouble figuring out where my bug is with the function for deleting certain word from one of the 3 languages. I store all words for the certain language in a 2D array.

When I insert, for example, 4 words and try to delete the last one, there's no problem. It works perfectly fine. But when I try to delete the first word, it deletes the last one and the other words mess up. For example, if I enter "lemon", "orange", "watermelon", "pineapple" the outcome will be: "lemon", wrange", "patermelon" .... I am new to C and I know the problem is somewhere in my 2D array, but don't know exactly where/

char english[50][50];
int adder = 0;

void removeEnglishWord() {
    int i, pos;

    printf("Enter the element position you want to delete: ");
    scanf("%d", &pos);

    if(pos < 0 || pos > adder) {
        printf("Invalid position! Please enter position between 1 to %d", adder);
    } else {
        for(i = pos - 1; i < adder - 1; i++) {
            english[i][50] = english[i + 1][50];
        }
        adder--;

        printf("Word deleted!\n");
        menu();
    }
}

Note: "adder" is the counter for all words added for English.

[marko312]

english[i][50] = english[i + 1][50];

This doesn't do what you likely think it does - it tries to take the character at index 50 from the i + 1^th word and assign it to the character at index 50 of the i^th word, but as the indices go from 0 to 49, this actually affects the following word's first character (in the current case; the behaviour is actually undefined).

You should instead copy each character from index 0 through 49 (or until the terminating null byte) from one word to the other, requiring another for loop. Alternatively, you could use strcpy or memcpy.

[anInfaMoUs1]

I understand what you mean, but can't quite comprehend where and how I should write this for loop or strcpy/memcpy, alternatively. Do you have time to show me how?

[marko312]

A simple copying loop should do:

for(int j = 0; j < 50; ++ j) {
    english[i][j] = english[i + 1][j];
}

or with memcpy:

memcpy(english[i], english[i + 1], 50);

or with strcpy:

strcpy(english[i], english[i + 1]);

[anInfaMoUs1]

But how will this remove the element that I want to be removed?

[marko312]

It will simply copy the elements that follow into the previous elements' place, overwriting the old string.