81 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			81 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| ---
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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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| 
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| # --description--
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| 
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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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| 
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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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| 
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| # --hints--
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| 
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| `selfPowers(10, 3)` should return a number.
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| 
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| ```js
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| assert(typeof selfPowers(10, 3) === 'number');
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| ```
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| 
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| `selfPowers(10, 3)` should return 317.
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| 
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| ```js
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| assert.strictEqual(selfPowers(10, 3), 317);
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| ```
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| 
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| `selfPowers(150, 6)` should return 29045.
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| 
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| ```js
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| assert.strictEqual(selfPowers(150, 6), 29045);
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| ```
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| 
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| `selfPowers(673, 7)` should return 2473989.
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| 
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| ```js
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| assert.strictEqual(selfPowers(673, 7), 2473989);
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| ```
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| 
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| `selfPowers(1000, 10)` should return 9110846700.
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| 
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| ```js
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| assert.strictEqual(selfPowers(1000, 10), 9110846700);
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| ```
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| 
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| # --seed--
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| 
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| ## --seed-contents--
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| 
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| ```js
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| function selfPowers(power, lastDigits) {
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| 
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|   return true;
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| }
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| 
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| selfPowers(1000, 10);
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| ```
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| 
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| # --solutions--
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| 
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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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| 
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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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| 
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|     sum += temp;
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|     sum %= modulo;
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|   }
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| 
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|   return sum;
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| }
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| ```
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