Hay dien cac so 1;-1;2;-2;3;-3 vao cac o trong trong hinh vuong ben (moi so vao 1 o) sao cho tong ba so tren moi dong,moi cot hoac moi duong cheo deu bang nhau
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|__________|________|_______|
|__________|________|_____5__|
|____4______|________|______0_|