Fix typos.

Author: trekhleb

README.md

@@ -150,6 +150,7 @@ algorithm is an abstraction higher than a computer program.
   * `B` [Rain Terraces](src/algorithms/uncategorized/rain-terraces) - trapping rain water problem
   * `A` [Maximum Subarray](src/algorithms/sets/maximum-subarray)
   * `A` [Travelling Salesman Problem](src/algorithms/graph/travelling-salesman) - shortest possible route that visits each city and returns to the origin city
+  * `A` [Discrete Fourier Transform](src/algorithms/math/fourier-transform) - decompose a function of time (a signal) into the frequencies that make it up
 * **Greedy** - choose the best option at the current time, without any consideration for the future
   * `B` [Jump Game](src/algorithms/uncategorized/jump-game)
   * `A` [Unbound Knapsack Problem](src/algorithms/sets/knapsack-problem)

src/algorithms/math/fourier-transform/discreteFourierTransform.js

@@ -11,7 +11,7 @@ import ComplexNumber from '../complex-number/ComplexNumber';
  */
 export default function discreteFourierTransform(inputSignalAmplitudes) {
   const N = inputSignalAmplitudes.length;
-  const outpuFrequencies = [];
+  const outputFrequencies = [];
 
   // For every frequency discrete...
   for (let frequencyValue = 0; frequencyValue < N; frequencyValue += 1) {
@@ -48,8 +48,8 @@ export default function discreteFourierTransform(inputSignalAmplitudes) {
     // Average contribution at this frequency
     signal = signal.divide(N);
 
-    outpuFrequencies[frequencyValue] = signal;
+    outputFrequencies[frequencyValue] = signal;
   }
 
-  return outpuFrequencies;
+  return outputFrequencies;
 }