zigzag数组是JPEG编码里取像素数据的排列顺序，用户输入n，程序就可以实现规定矩阵沿45度线递增，形成一个zigzag数组-zigzag array is arranged in order to take the pixel JPEG encoded data, the user input n, the program can be achieved along the 45 degree line matrix specified increments to form a zigza