Given a list of stones' positions (in units) in sorted ascending order, determine if the frog is able to cross the river by landing on the last stone.

给定一列石头的位置(以单元数计)，顺序递增，判断青蛙是否可以跳到最后一块石头上。

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There was a stone cross in the middle of the village.

村子中间有一块十字形石碑。

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The individual columns never appear singly but occur as a succession of interpenetrations that in cross section make a zigzag suture across the face of the stone.

单个的石柱从不单独出现，而只作为一系列相互穿插的部分在岩石的横截面上呈现出之字裂痕。

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The most you can expect by way of scene-setting here are occasional keen-eyed observations by Jesse Stone, the hero, of the women who cross his line of sight.

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In the courtyard, the stone St Patrick's cross replicates the worn original in the Rock of Cashel's 15th-century Hall of the Vicars Choral, which was built to house the cathedral's male choristers.

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