And she wept before him the seven days, while their feast lasted: and it came to pass on the seventh day, that he told her, because she pressed him sore; and she told the riddle to the children of her people. (ASV)
According to the text, Samson's wedding feast was to last seven days (verse 12), and Samson gave his guests those seven days to solve his riddle.
On the seventh day (verse 15) of the feast—the last day before they lose the bet—they still have no answer, so they lean on Samson's fiancée to find out the answer. She then cries for seven more days (verse 17) until Samson relents and tells her. She then tells the guests, and they win the riddle, enraging Samson. The glaring contradiction is that they should have lost, because they missed their deadline by at least six days, since it took seven days beginning with the last day of the feast for Samson's nameless bride to coax out the answer.
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