Program 1 - 2D array and memory pointers, C (gcc)

Program 1 - 2D array and memory pointers

//gcc 5.4.0

#include  <stdio.h>

int main(void)
{
    int *myPtr;
    int myArray[4][4];
    int i;
    int k;
    int *temp;
    int *rowPtr[4];
        
    //Printing column by column
    printf("Printing 2D array column by column: \n");
    myPtr = &(myArray[0][0]);
    
    for(i = 0; i < 4; i++){
        for(k = 0; k < 4; k++){
            *myPtr = k;
            printf("%d ", *myPtr);
            myPtr++;
        }
        printf("\n");
    } 
    printf("\n"); 
    
    //Printing row by row
    printf("Printing 2D array row by row: \n");
    myPtr = &(myArray[0][0]);
    
    for(i = 0; i < 4; i++){
        for(k = 0; k < 4; k++){
        
            *myPtr = i;
            printf("%d ", *myPtr);
            myPtr++;
        }
        printf("\n");
    }
    printf("\n");
    
    //Printing using printRow method
    printf("Printing 2D array using printRow method: \n");
    
    for(i = 0; i < 4; i++){
        printRow(&(myArray[i][0]), 4);
    }
    printf("\n");
    
    //Switching row 0 and row 3
    for(i = 0; i < 4; i++){
        rowPtr[i] = &(myArray[i][0]);
    }
    
    temp = rowPtr[0];
    rowPtr[0] = rowPtr[3];
    rowPtr[3] = temp;
    
    //Printing swapped rows
    printf("Printing array with row 0 and row 3 swapped: \n");
    
    for(i = 0; i < 4; i++){
        printRow(rowPtr[i], 4);
    }
}

void printRow(int *r, int nCols){
    int i;
    int *myPtr;
    
    myPtr = r;
    for(i = 0; i < nCols; i++){
        printf("%d ", *myPtr);
        myPtr++;
    }
    printf("\n");
    
}


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