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2025-01-30 05:57:25 2025-01-30 05:57:25 2025-01-30 05:57:25 2025-01-30 05:57:25 2025-01-30 05:57:25 2025-01-30 05:57:25 2025-01-30 05:57:25 2025-01-30 05:57:25 2025-01-30 05:57:25 2025-01-30 05:57:25现需一个钢结构屋顶采用人字梁仓库宽5米长31米每隔5米设置一根柱子请问该如何下料
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