ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
92 lines
2.9 KiB
Markdown
92 lines
2.9 KiB
Markdown
---
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id: 5900f37e1000cf542c50fe91
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title: 问题18：最大路径总和I.
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challengeType: 5
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videoUrl: ''
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dashedName: problem-18-maximum-path-sum-i
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---
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# --description--
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通过启动在低于该三角形的顶部和移动到相邻的数字下面的行中，最大总从上到下为23 **3**
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**7** 4
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2 **4** 6
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8 5 **9** 3也就是说，3 + 7 + 4 + 9 = 23.找到下面三角形从上到下的最大总数： 75
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95 64
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17 47 82
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18 35 87 10
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20 04 82 47 65
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19 01 23 75 03 34
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88 02 77 73 07 63 67
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99 65 04 28 06 16 70 92
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41 41 26 56 83 40 80 70 33
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41 48 72 33 47 32 37 16 94 29
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53 71 44 65 25 43 91 52 97 51 14
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70 11 33 28 77 73 17 78 39 68 17 57
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91 71 52 38 17 14 91 43 58 50 27 29 48
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63 66 04 68 89 53 67 30 73 16 69 87 40 31
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04 62 98 27 23 09 70 98 73 93 38 53 60 04 23 **注意：** 由于只有16384条路线，因此可以通过尝试每条路线来解决此问题。然而，问题67，与包含一百行的三角形是同样的挑战;它无法通过蛮力解决，需要一种聪明的方法！ ; O）
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# --hints--
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`maximumPathSumI(testTriangle)`应该返回23。
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```js
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assert.strictEqual(maximumPathSumI(testTriangle), 23);
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```
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`maximumPathSumI(numTriangle)`应该返回1074。
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```js
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assert.strictEqual(maximumPathSumI(numTriangle), 1074);
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```
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# --seed--
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## --before-user-code--
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```js
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const numTriangle = [[75, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [95, 64, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [17, 47, 82, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [18, 35, 87, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [20, 4, 82, 47, 65, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [19, 1, 23, 75, 3, 34, 0, 0, 0, 0, 0, 0, 0, 0, 0], [88, 2, 77, 73, 7, 63, 67, 0, 0, 0, 0, 0, 0, 0, 0], [99, 65, 4, 28, 6, 16, 70, 92, 0, 0, 0, 0, 0, 0, 0], [41, 41, 26, 56, 83, 40, 80, 70, 33, 0, 0, 0, 0, 0, 0], [41, 48, 72, 33, 47, 32, 37, 16, 94, 29, 0, 0, 0, 0, 0], [53, 71, 44, 65, 25, 43, 91, 52, 97, 51, 14, 0, 0, 0, 0], [70, 11, 33, 28, 77, 73, 17, 78, 39, 68, 17, 57, 0, 0, 0], [91, 71, 52, 38, 17, 14, 91, 43, 58, 50, 27, 29, 48, 0, 0], [63, 66, 4, 68, 89, 53, 67, 30, 73, 16, 69, 87, 40, 31, 0], [4, 62, 98, 27, 23, 9, 70, 98, 73, 93, 38, 53, 60, 4, 23]];
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```
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## --seed-contents--
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```js
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function maximumPathSumI(triangle) {
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return true;
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}
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const testTriangle = [[3, 0, 0, 0],
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[7, 4, 0, 0],
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[2, 4, 6, 0],
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[8, 5, 9, 3]];
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maximumPathSumI(testTriangle);
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```
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# --solutions--
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```js
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const testTriangle = [[3, 0, 0, 0],
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[7, 4, 0, 0],
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[2, 4, 6, 0],
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[8, 5, 9, 3]];
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function maximumPathSumI(triangle) {
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let maxSum = triangle.slice();
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for (let i = triangle.length - 1; i > 0; i--) {
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let currentRow = maxSum[i];
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let previousRow = maxSum[i - 1];
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const temp = [];
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for (let j = 0; j < i; j++) {
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temp.push(Math.max((currentRow[j] + previousRow[j]), (currentRow[j + 1] + previousRow[j])));
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}
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maxSum[i - 1] = temp;
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maxSum.pop();
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}
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return maxSum[0][0];
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}
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```
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