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38 lines
1.5 KiB
HTML
38 lines
1.5 KiB
HTML
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<p>Hercy wants to save money for his first car. He puts money in the Leetcode bank <strong>every day</strong>.</p>
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<p>He starts by putting in <code>$1</code> on Monday, the first day. Every day from Tuesday to Sunday, he will put in <code>$1</code> more than the day before. On every subsequent Monday, he will put in <code>$1</code> more than the <strong>previous Monday</strong>.<span style="display: none;"> </span></p>
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<p>Given <code>n</code>, return <em>the total amount of money he will have in the Leetcode bank at the end of the </em><code>n<sup>th</sup></code><em> day.</em></p>
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<p> </p>
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<p><strong>Example 1:</strong></p>
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<pre>
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<strong>Input:</strong> n = 4
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<strong>Output:</strong> 10
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<strong>Explanation:</strong> After the 4<sup>th</sup> day, the total is 1 + 2 + 3 + 4 = 10.
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</pre>
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<p><strong>Example 2:</strong></p>
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<pre>
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<strong>Input:</strong> n = 10
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<strong>Output:</strong> 37
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<strong>Explanation:</strong> After the 10<sup>th</sup> day, the total is (1 + 2 + 3 + 4 + 5 + 6 + 7) + (2 + 3 + 4) = 37. Notice that on the 2<sup>nd</sup> Monday, Hercy only puts in $2.
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</pre>
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<p><strong>Example 3:</strong></p>
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<pre>
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<strong>Input:</strong> n = 20
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<strong>Output:</strong> 96
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<strong>Explanation:</strong> After the 20<sup>th</sup> day, the total is (1 + 2 + 3 + 4 + 5 + 6 + 7) + (2 + 3 + 4 + 5 + 6 + 7 + 8) + (3 + 4 + 5 + 6 + 7 + 8) = 96.
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</pre>
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<p> </p>
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<p><strong>Constraints:</strong></p>
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<ul>
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<li><code>1 <= n <= 1000</code></li>
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</ul>
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