\u7ed9\u4f60\u4e00\u4e2a\u6574\u6570\u6570\u7ec4 nums \uff0c\u5224\u65ad\u8fd9\u4e2a\u6570\u7ec4\u4e2d\u662f\u5426\u5b58\u5728\u957f\u5ea6\u4e3a 3 \u7684\u9012\u589e\u5b50\u5e8f\u5217\u3002<\/p>\n\n\n\n
\u5982\u679c\u5b58\u5728\u8fd9\u6837\u7684\u4e09\u5143\u7ec4\u4e0b\u6807 (i, j, k) \u4e14\u6ee1\u8db3 i < j < k \uff0c\u4f7f\u5f97 nums[i] < nums[j] < nums[k] \uff0c\u8fd4\u56de true \uff1b\u5426\u5219\uff0c\u8fd4\u56de false \u3002<\/p>\n\n\n\n
<\/p>\n\n\n\n
\u5341\u5206\u949f\u5199\u51fa\u6765\u7684\u8d39\u65f6\u8d39\u7a7a\u95f4\u89e3\u6cd5\uff1a<\/p>\n\n\n\n
class Solution:\n def increasingTriplet(self, nums: List[int]) -> bool:\n n = len(nums)\n if n < 3:\n return False\n ## DP1 \u52a8\u6001\u89c4\u5212\uff0c\u5b9a\u4e49\u7b2ci\u4e2a\u503c\u4e3a\u5728\u8fd9\u4e2a\u6570\u5de6\u8fb9\u542b\u8fd9\u4e2a\u6570\u80fd\u8fbe\u5230\u7684\u6700\u5c0f\u503c\n dp1 = [nums[0]] * n\n for i in range(1,n):\n dp1[i] = min(dp1[i-1], nums[i])\n ## DP2 \u52a8\u6001\u89c4\u5212\uff0c\u5b9a\u4e49\u7b2ci\u4e2a\u503c\u4e3a\u5728\u8fd9\u4e2a\u6570\u53f3\u8fb9\u542b\u8fd9\u4e2a\u6570\u80fd\u8fbe\u5230\u7684\u6700\u5927\u503c\n dp2 = [nums[-1]] * n\n for i in range(n-2,-1,-1):\n dp2[i] = max(dp2[i+1], nums[i])\n \n for i in range(n):\n if nums[i] > dp1[i] and nums[i] < dp2[i]:\n return True\n return False<\/pre>\n\n\n\n\u6267\u884c\u7528\u65f6\uff1a<\/strong>224 ms, \u5728\u6240\u6709\u00a0Python3\u00a0\u63d0\u4ea4\u4e2d\u51fb\u8d25\u4e867.07%\u7684\u7528\u6237<\/p>\n\n\n\n
\u5185\u5b58\u6d88\u8017\uff1a<\/strong>27.5 MB, \u5728\u6240\u6709\u00a0Python3\u00a0\u63d0\u4ea4\u4e2d\u51fb\u8d25\u4e865.12%\u7684\u7528\u6237<\/p>\n\n\n\n
\u5176\u5b9e\u4e5f\u5c31\u662f\u5b98\u65b9\u6807\u7b54\u7684\u53cc\u5411\u904d\u5386\u6cd5\uff1a<\/strong><\/p>\n\n\n\n
class Solution:\n def increasingTriplet(self, nums: List[int]) -> bool:\n n = len(nums)\n if n < 3:\n return False\n leftMin = [0] * n\n leftMin[0] = nums[0]\n for i in range(1, n):\n leftMin[i] = min(leftMin[i - 1], nums[i])\n rightMax = [0] * n\n rightMax[n - 1] = nums[n - 1]\n for i in range(n - 2, -1, -1):\n rightMax[i] = max(rightMax[i + 1], nums[i])\n for i in range(1, n - 1):\n if leftMin[i - 1] < nums[i] < rightMax[i + 1]:\n return True\n return False<\/pre>\n\n\n\n\u8d2a\u5fc3\u7b97\u6cd5\uff1a<\/strong><\/p>\n\n\n\n
class Solution:\n def increasingTriplet(self, nums: List[int]) -> bool:\n n = len(nums)\n if n < 3:\n return False\n first, second = nums[0], float('inf')\n for i in range(1, n):\n num = nums[i]\n if num > second:\n return True\n if num > first:\n second = num\n else:\n first = num\n return False<\/pre>\n\n\n\n\u8d2a\u5fc3\u7b97\u6cd5\u6bd4\u8f83\u5de7\u7684\u4e00\u70b9\u5c31\u662f\uff0c\u51fa\u73b0\u7b2c\u4e09\u4e2a\u6570\u7684\u60c5\u51b5\u3002\u57fa\u4e8e\u7b2c\u4e09\u4e2a\u6570\u4e00\u5b9a\u4f1a\u6bd4\u7b2c\u4e8c\u4e2a\u6570\u5c0f\uff0c\u6240\u4ee5\u53ef\u4ee5\u53d6\u7f14\u7b2c\u4e8c\u4e2a\u6570\u6216\u8005\u7b2c\u4e00\u4e2a\u6570\u3002<\/p>\n\n\n\n