Nth fibonacci number exercise (#5)

data-structures-and-algorithms/nth-fibonacci-number/answer/README.md

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+# Nth fibonacci number
+
+The Fibonacci numbers are the numbers in the following integer sequence: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, ...
+
+Given a number n, print n-th Fibonacci Number. 
+
+Examples:
+
+```
+Input: 0
+Output: 0
+
+Input: 1
+Output: 1
+
+Input: 2
+Output: 1
+
+Input: 3
+Output: 2
+
+Input: 9
+Output: 34
+```

data-structures-and-algorithms/nth-fibonacci-number/answer/nth-fibonacci-number.js

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+const assert = require('assert');
+
+function nthFibonacciNumber(n) {
+  if (n == 0) {
+    return 0;
+  }
+
+  if (n == 1) {
+    return 1;
+  }
+
+  let secondLast = 0;
+  let last = 1;
+  let current = null;
+  for (let i = 1; i < n; i++) {
+    current = secondLast + last;
+    secondLast = last;
+    last = current;
+  }
+
+  return last;
+}
+
+assert.equal(nthFibonacciNumber(0), 0);
+assert.equal(nthFibonacciNumber(1), 1);
+assert.equal(nthFibonacciNumber(2), 1);
+assert.equal(nthFibonacciNumber(3), 2);
+assert.equal(nthFibonacciNumber(9), 34);
+
+console.log("All assertions passed!");

data-structures-and-algorithms/nth-fibonacci-number/exercise/README.md

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+# Nth fibonacci number
+
+The Fibonacci numbers are the numbers in the following integer sequence: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, ...
+
+Given a number n, print n-th Fibonacci Number. 
+
+Examples:
+
+```
+Input: 0
+Output: 0
+
+Input: 1
+Output: 1
+
+Input: 2
+Output: 1
+
+Input: 3
+Output: 2
+
+Input: 9
+Output: 34
+```

data-structures-and-algorithms/nth-fibonacci-number/exercise/nth-fibonacci-number.js

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+const assert = require('assert');
+
+function nthFibonacciNumber(n) {
+}
+
+assert.equal(nthFibonacciNumber(0), 0);
+assert.equal(nthFibonacciNumber(1), 1);
+assert.equal(nthFibonacciNumber(2), 1);
+assert.equal(nthFibonacciNumber(3), 2);
+assert.equal(nthFibonacciNumber(9), 34);
+
+console.log("All assertions passed!");