{ "data": { "question": { "questionId": "2249", "questionFrontendId": "2145", "boundTopicId": null, "title": "Count the Hidden Sequences", "titleSlug": "count-the-hidden-sequences", "content": "

You are given a 0-indexed array of n integers differences, which describes the differences between each pair of consecutive integers of a hidden sequence of length (n + 1). More formally, call the hidden sequence hidden, then we have that differences[i] = hidden[i + 1] - hidden[i].

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You are further given two integers lower and upper that describe the inclusive range of values [lower, upper] that the hidden sequence can contain.

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Return the number of possible hidden sequences there are. If there are no possible sequences, return 0.

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Example 1:

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\nInput: differences = [1,-3,4], lower = 1, upper = 6\nOutput: 2\nExplanation: The possible hidden sequences are:\n- [3, 4, 1, 5]\n- [4, 5, 2, 6]\nThus, we return 2.\n
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Example 2:

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\nInput: differences = [3,-4,5,1,-2], lower = -4, upper = 5\nOutput: 4\nExplanation: The possible hidden sequences are:\n- [-3, 0, -4, 1, 2, 0]\n- [-2, 1, -3, 2, 3, 1]\n- [-1, 2, -2, 3, 4, 2]\n- [0, 3, -1, 4, 5, 3]\nThus, we return 4.\n
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Example 3:

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\nInput: differences = [4,-7,2], lower = 3, upper = 6\nOutput: 0\nExplanation: There are no possible hidden sequences. Thus, we return 0.\n
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Constraints:

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Notice that we can then determine all the other elements of the sequence by using the differences array.", "We will also be able to determine the difference between the minimum and maximum elements of the sequence. Notice that the value of x does not affect this.", "We now have the ‘range’ of the sequence (difference between min and max element), we can then calculate how many ways there are to fit this range into the given range of lower to upper.", "Answer is (upper - lower + 1) - (range of sequence)" ], "solution": null, "status": null, "sampleTestCase": "[1,-3,4]\n1\n6", "metaData": "{\n \"name\": \"numberOfArrays\",\n \"params\": [\n {\n \"name\": \"differences\",\n \"type\": \"integer[]\"\n },\n {\n \"type\": \"integer\",\n \"name\": \"lower\"\n },\n {\n \"type\": \"integer\",\n \"name\": \"upper\"\n }\n ],\n \"return\": {\n \"type\": \"integer\"\n }\n}", "judgerAvailable": true, "judgeType": "large", "mysqlSchemas": [], "enableRunCode": true, "enableTestMode": false, "enableDebugger": true, "envInfo": "{\"cpp\": [\"C++\", \"

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