81 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			81 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
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								---
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								id: 5900f39c1000cf542c50feaf
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								title: 'Problem 48: Self powers'
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								challengeType: 5
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								forumTopicId: 302157
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								dashedName: problem-48-self-powers
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								---
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								# --description--
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								The series, 1<sup>1</sup> + 2<sup>2</sup> + 3<sup>3</sup> + ... + 10<sup>10</sup> = 10405071317.
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								Find the last ten digits of the series, 1<sup>1</sup> + 2<sup>2</sup> + 3<sup>3</sup> + ... + 1000<sup>1000</sup>.
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								# --hints--
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								`selfPowers(10, 3)` should return a number.
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								```js
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								assert(typeof selfPowers(10, 3) === 'number');
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								```
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								`selfPowers(10, 3)` should return 317.
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								```js
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								assert.strictEqual(selfPowers(10, 3), 317);
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								```
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								`selfPowers(150, 6)` should return 29045.
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								```js
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								assert.strictEqual(selfPowers(150, 6), 29045);
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								```
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								`selfPowers(673, 7)` should return 2473989.
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								```js
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								assert.strictEqual(selfPowers(673, 7), 2473989);
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								```
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								`selfPowers(1000, 10)` should return 9110846700.
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								```js
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								assert.strictEqual(selfPowers(1000, 10), 9110846700);
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								```
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								# --seed--
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								## --seed-contents--
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								```js
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								function selfPowers(power, lastDigits) {
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								  return true;
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								}
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								selfPowers(1000, 10);
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								```
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								# --solutions--
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								```js
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								function selfPowers(power, lastDigits) {
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								  let sum = 0;
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								  const modulo = Math.pow(10, lastDigits);
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								  for (let i = 1; i <= power; i++) {
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								    let temp = i;
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								    for (let j = 1; j < i; j++) {
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								      temp *= i;
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								      temp %= modulo;
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								    }
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								    sum += temp;
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								    sum %= modulo;
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								  }
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								  return sum;
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								}
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								```
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