Clash Royale CLAN TAG#URR8PPP

Addressing multidimensional arrays in C

what is the problem? i think there's no logic problem or compile error

but the loop suddenly stopped after looping 16 times...

is this gcc compiler's error? i almost freaked out ...

like there's no compile error that pops up but doesn't work,,,

thanks in advance : ) sorry for the editing question

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#define RIGHT 0
#define DOWN 1
#define LEFT 2
#define UP 3

int main()

int x,y;
scanf("%d %d", &x, &y);

int **arr;
arr = (int**)malloc(sizeof(int*)*x);
for(int i = 0; i < x; i++) arr[i] = (int*)malloc(sizeof(int) * y );

int x_ = 0, y_ = 0;
int MAX_x = x-1;
int MAX_y = y-1;
int MIN_x = 0;
int MIN_y = 0;
int direction = RIGHT;
int num = 0;

while(true)


arr[x_][y_] = num++;

printf("%d", num);
//printf("%d", arr[x_][y_]);

switch ( direction )


case RIGHT:
if( y_ == MAX_y )

direction = DOWN; MIN_x ++; x_++;

else

y_++;

break;

case DOWN:
if( x_ == MAX_x )

direction = LEFT; MAX_y --; y_--;

else

x_++;

break;

case LEFT:
if( y_ == MIN_y )

direction = UP; MAX_x --; x_++;

else

y_--;

break;

case UP:
if( x_ == MIN_x )

direction = RIGHT; MIN_y ++; y_++;

else

x_++;

break;

default : break;



if(num == x * y )
break;



for(int i = 0; i < x; i ++)

for(int j = 0; j < y; j ++ )

printf("%3d", arr[i][j]);

printf("n");




numberOfRows

numberOfColumns

rowIndex

columnIndex

x_

y_

x

y

int arr[x][y];

1 Answer
1

In your case LEFT you want to decrement x_, not increment it. change your x_++ to x_--.

case LEFT

x_

x_++

x_--

In your case UP you also want to decrement, so change that x_++ to x_--.

case UP

x_++

x_--

I think your confusion here is that moving up requires a decrement, not an increment.

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