/*************************************************************
* Section 15
* M/c No : M
* Roll No : 18CS100XY
* Names : Anirban Ghose, Soumyajit Dey, Aritra Hazra
* Problem No : LT1-EVEN-1
* Description : Program to rotate an integer matrix clock-wise
**************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

// printing n x n matrix
void printMatrix(int **mat, int n)
{
    int i, j;
    for (i=0; i<n; i++) { 
        for (j=0; j<n; j++) {
            printf("%d\t", mat[i][j]);
        }
        printf("\n");
    }
}

// rotating n x n matrix clock-wise
void rotateClockwise(int **mat, int n)
{
    int i, j, temp;
    int start, end;
    
    for (i=0; i<n; i++) {
        for (j=i; j<n; j++) {
            temp = mat[i][j];
            mat[i][j] = mat[j][i];
            mat[j][i]=temp;
        }
    }
    for (i=0; i<n; i++) {
        start = 0; end = n-1;
        while ( start < end ) {
            temp = mat[i][start];
            mat[i][start] = mat[i][end];
            mat[i][end] = temp;
            start++; end--;
        }
    }
}

int main()
{
    int n, i, j, counter = 0;
    char exitYes[4], ch;
    int **sourceMatrix;
    
    printf("Enter Matrix Dimension (N): ");
    scanf("%d", &n);
    
    if (n < 1) { /* matrix having non-positive dimension */
        printf("No Elements to Enter. Check the Matrix Dimension!\n");
    }
    else {
        /* initialize source matrix */
        sourceMatrix = (int**)malloc(n*sizeof(int*));
        for (i=0; i<n; i++) {
            sourceMatrix[i] = (int*)malloc(n*(sizeof(int)));
        }
        
        /* scan integer input elements of matrix */
        printf("Enter %d Matrix Elements (Integers) in %dx%d Matrix: ", n*n, n, n);
        for (i=0; i<n; i++) {
            for (j=0; j<n; j++) {
                scanf("%d",&sourceMatrix[i][j]);
            }
        }
        
        /* print source matrix entered by user */
        printf("\n++ Your Entered Matrix:\n");
        printMatrix(sourceMatrix,n);
        
        ch = getchar();
        if ( (ch=getchar())=='\n' ) {
            while(1)
            {
                /* rotate source matrix and print */
                printf("\n++ The Clock-wise Rotated Matrix:\n");
                rotateClockwise(sourceMatrix, n);
                printMatrix(sourceMatrix,n);
                
                /* handling continue and terminate cases */
                printf("Press <Enter> to Continue OR Type \"exit\" to Terminate: ");
                counter = 0;
                while( (ch=getchar())!='\n' ) {
                    if( (counter == 0) && (ch == '\n') ) {
                        break;
                    }
                    exitYes[counter++] = ch;
                }
                if (counter && !strcmp(exitYes,"exit")) {
                    break;
                }
            }
        }
    }

    return 0;
}