how do i declare dynamic two dimension char array.

[hitmanner]

how do you declare an array of dynamic string.

i mean..if you have

char name[501][41];

how do u declare the above in dynamic mode using *.

char *name[41]?
or
char *name*?
thanks in advance;

[Lerner]

You have several options. Here's one:

char ** strings;
strings = new char* [501]; //display an array of 501 char pointers.
for(int i = 0; i < 501; ++i)
   strings[i] = new char[41]; //each of the 501 char pointers will have the address of the first char in an array of 41 char.

[StuXYZ]

Hi,

There is a tiny bit of a trick to doing this. Basically, you need to get enough memory for the characters AND enough memory for a pointers to it.

This assumes that both the 501 and 41 in your example are effectively variables that are only known at run time.
So

int m(501);   // obviously this can be set elsewhere
int n(41);      
...

char *tmpC=new char[m*n];
char **OutPtr=new char*[m];
 for (int i=0;i<m;i++)
    OutPtr[i]=tmpC + (i*n);

Now just use OutPtr. (or return it from a function).

Obviously, I had better give the delete method.
it is just

delete [] *OutPtr;
delete [] OutPtr;

Hope that helps.

[ArkM]

typedef char Name[41];
Name* name = new Name[501];
...
delete [] name;

[omeralper]

This is also 2 dimensional, pointers of pointers

float **grades;
int *examNo, studentNo, i, j;

cout << "No of students: "; 
cin >> studentNo; 

grades = new float *[studentNo];
examNo = new int [studentNo];
for (i = 0; i < studentNo; i++){
    cout << "No of exams for " << i;
    cin >> examNo[i];
    grades[i] = new float[examNo[i]];
    for (j = 0; j < examNo[i]; j++)
        grades[i][j] = 0;
}
for (i = 0; i < studentNo; i++)
    delete [] grades[i];
delete [] grades;
delete [] examNo;

This is array of pointers

const int size = 6;
int *triangle[size], i, j;
	
for (i = 0; i < size; i++){
    triangle[i] = new int[i+1];
    for (j = 0; j < i+1; j++)
        triangle[i][j] = i+1;
}
for (i = 0; i < size; i++){
    for (j = 0; j < i+1; j++)
        cout << triangle[i][j];
    cout << endl;
}
for (i = 0; i < size; i++)
    delete [] triangle[i];

And pointers of array

double (*points)[2];
int i, j, pointNo;

cout << "Number of points: ";
cin >> pointNo;
points = new (double[pointNo])[2];
for (i = 0; i < pointNo; i++){
    cout << "Enter x coordinate: ";
    cin >> points[i][0];
    cout << "Enter y coordinate: ";
    cin >> points[i][1];
}
for (i = 0; i < pointNo; i++){
    cout << "x: " << points[i][0];
    cout << ", y: " << points[i][1] << endl;
}
delete []points;

[amin_a]

char** chpp = (char**) malloc(sizeof(char));
char* chp = "aaa";
chpp[0] = chp;
chp = "bbb";
chpp[1] = chp;
chp = "ccc";
chpp[2] = chp;
for(int i=0; i<3; i++)
cout << chpp << endl;

I've tried to write it simple. However you can expand it and use it in a loop.