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/**
 * Note: The returned array must be malloced, assume caller calls free().
 */

#define MIN(a, b) ((a) > (b) ? (b) : (a))
int* spiralOrder(int** matrix, int matrixRowSize, int matrixColSize) {
	int* result = malloc(matrixRowSize * matrixColSize);
	int index = 0;
	int offset;
	int maxOffset = MIN(matrixRowSize, matrixColSize) / 2 + 1;

	for(offset = 0; offset < maxOffset; offset++, matrixColSize--, matrixRowSize--) {
		if(matrixRowSize == 0 || matrixColSize == 0)
			break;
		else if(matrixRowSize == 1) {
			for(int i = 0; i < matrixColSize; i++)
				result[index++] = matrix[offset][offset + i];
			break;
		} else if(matrixColSize == 1) {
			for(int i = 0; i < matrixRowSize; i++)
				result[index++] = matrix[offset + i][offset];
			break;
		} else {
			for(int i = 0; i < matrixColSize; i++)
				result[index++] = matrix[offset][offset + i];
			for(int i = 1; i < matrixRowSize; i++)
				result[index++] = matrix[offset + i][offset + matrixColSize - 1];
			for(int i = 1; i < matrixColSize; i++)
				result[index++] = matrix[offset + matrixRowSize - 1][offset + matrixColSize - 1 - i];
			for(int i = 1; i < matrixRowSize - 1; i++)
				result[index++] = matrix[offset + matrixRowSize - 1 - i][offset];
		}
	}

	return result;
}