请设计算法，使用至多4种不同颜色对七巧板进行涂色（每块涂一种颜色），要求相邻区域的颜色互不相同，打印输出所有可能的方案。

提示：可以把七巧板上的每个区域看成一个顶点，若两个区域相邻，则相应的顶点间用一条边相连，这样将七巧板转换为图，该问题实质上是一个图的搜索问题。

-Please design algorithm, using up to 4 different colors for coloring on the puzzle (each block of color coated), asked the color of adjacent regions with each other, print out all possible scenarios. Tip: You can put the jigsaw puzzle on each region as a vertex, if the two regions adjacent to, the corresponding vertices connected with an edge, so the puzzle is converted to graph, the problem is essentially a graph search problem.