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passing 2d arrays

I have a question in my codes. Can anyone help me?

void print(char S[], char * * path, int i, int j) {
    if (i == 0 || j == 0) return;
    if (path[i][j] == 'c') {
        print(S, path, i - 1, j - 1);
        cout << S[i];
    }
    else if (path[i][j] == 'u') print(S, path, i - 1, j);
    else print(S, path, i, j - 1);
}
int LongestCommonSubsequence(char S[], char T[]) {
    int Slength = strlen(S);
    int Tlength = strlen(T); /* Starting the index from 1 for our convinience (avoids handling special cases for negative indices) */
    int i, j;
    char path[Slength][Tlength];
    int common[Slength][Tlength];
    for (i = 0; i <= Tlength; i++) {
        common[0][i] = 0;
    } /*common[i][0]=0, for all i because there are no characters from string T*/
    for (i = 0; i <= Slength; i++) {
        common[i][0] = 0;
    }
    for (i = 1; i <= Slength; i++) {
        for (j = 1; j <= Tlength; j++) {
            if (S[i] == T[j]) {
                common[i][j] = common[i - 1][j - 1] + 1;
                path[i][j] = 'c';
            }
            else if (common[i - 1][j] >= common[i][j - 1]) {
                common[i][j] = common[i - 1][j];
                path[i][j] = 'u';
            }
            else {
                common[i][j] = common[i][j - 1];
                path[i][j] = 'l';
            }

        }
    }
    print(S, path, Slength, Tlength); // it gives an Error!!!!
    return common[Slength][Tlength];

}

My error is in:

print(S,path,Slength,Tlength);

And It gives:

cannot convert “char ()[((unsigned int)((int)Tlength))]' to \``char**‘ for argument `2’ to “void print(char, char**, int, int)’`

What should I do?

Answer 1

Here is your problem:

char path[Slength][Tlength];
int common[Slength][Tlength];

(where Slength and Tlength are non-constant expressions)

Variable-length arrays are illegal. The C++ standard requires constant integral expressions for array bounds in declarations (in a new[] expression, the outermost bound can be variable).

Note to voters: The OP marked his question as C++, someone else changed the tags, no idea what compiler is actually in use.