Double pointer can be used to point to two dimensional matrix (pointer-to-pointer). If there are more than one matrices and it is required to keep track of these matrices then an additional extra pointer will be required. At his point triple-pointers can be used to point to list of two dimensional matrices.
We assume that you have got three different two-dimensional matrices as in the below picture:
Triple pointer with size of 3 and pointing to 3 different matrices:
#include <QCoreApplication> #include <iostream> using namespace std; //function prototype int** initializeMatrix(int** tempMatrix, int row, int column, int matrixCellValue); int main(int argc, char *argv[]) { QCoreApplication a(argc, argv); int size = 3; int*** triplePointer; //Allocate memory for triplePointer triplePointer = new int**[size]; int rowNum = 4; int columnNum = 3; int** newMatrix = 0; //Assign elements to cell values of each matrix for(int i=0; i<size; i++) triplePointer[i] = initializeMatrix(newMatrix,rowNum,columnNum,i); //Print elements of allocated matrices for(int num = 0; num<size; num++) { for(int i=0; i<rowNum; i++) { for(int j=0; j<columnNum; j++) { cout<<triplePointer[num][i][j]; } cout << "\n"; } cout << "\n"; } return a.exec(); } /* tempMatrix: matrix to allocate row: number of rows of the matrix column: number of columns of the matrix matrixCellValue: value to assign to specified cell of matrix */ int** initializeMatrix(int** tempMatrix, int row, int column, int matrixCellValue) { tempMatrix = new int*[row]; for(int i=0; i<row; i++) tempMatrix[i] = new int[column]; for(int i=0; i<row; i++) for(int j=0; j<column; j++) tempMatrix[i][j] = matrixCellValue; return tempMatrix; }
Sample c++ console application built with qt-creator on ubuntu and the console-output is 3 different 2x2 matrices displayed. Same output is produced when built with MSVS2008 on winXP.
good work man...helped a lot... :)
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