A和B的道路:
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"H G:by
"H G:by
│←───28段────→│
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┌─┬─┬─┬─┬─┬─┐B ─
"H G:by
├─┼─┼─┼─┼─┼─┤ ↑
"H G:by
├─┼─┼─┼─┼─┼─┤ │
"H G:by
├─┼─┼─┼─┼─┼─┤ │
"H G:by
├─┼─┼─┼─┼─┼─┤ 29段
"H G:by
├─┼─┼─┼─┼─┼─┤ │
"H G:by
├─┼─┼─┼─┼─┼─┤ │
"H G:by
├─┼─┼─┼─┼─┼─┤ │
"H G:by
├─┼─┼─┼─┼─┼─┤ ↓
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└─┴─┴─┴─┴─┴─┘ ─
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A
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如果只能向上和向右走,由A走到B共有多少个走法?(答案须准确至个位)
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今天老师给了这道题目
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我不知道怎样做...
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呜呜~~~有谁能帮我呢??
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如果答对了我会奖赏[SIZE="5"][COLOR="Red"]200蕊迷币[/COLOR][/SIZE]的
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帮帮我可以吗pleas