我前两天发了一个帖子问怎么判断碎片图形能不能拼在一起的，后来老师说了一个重要条件，就碎片是图形是从一个完整的矩形里取出来的，只可能少，不可能多，所以，我想计算面积来判断能不能拼在一起。
请大家指教下怎么计算类似于下图的不规则图形的面积，如图，同行星间距是2，同列星间距是1，斜边是坐标各加1。

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