Prep exersises from 2d week of JS

vlnach · vlnach · commit eeb5127634bb · 2025-05-16T19:05:46.000+02:00
diff --git a/Week2/prep-exercises/1-traffic-light/traffic-light.js b/Week2/prep-exercises/1-traffic-light/traffic-light.js
@@ -9,6 +9,7 @@ function getCurrentState(trafficLight) {
   // TODO
   // Should return the current state (i.e. colour) of the `trafficLight`
   // object passed as a parameter.
+  return trafficLight.possibleStates[trafficLight.stateIndex];
 }
 
 function getNextStateIndex(trafficLight) {
@@ -17,8 +18,14 @@ function getNextStateIndex(trafficLight) {
   // - if the color is green, it will turn to orange
   // - if the color is orange, it will turn to red
   // - if the color is red, it will turn to green
+  if (getCurrentState(trafficLight) === "green") {
+    return 1;
+  } else if (getCurrentState(trafficLight) === "orange") {
+    return 2;
+  } else if (getCurrentState(trafficLight) === "red") {
+    return 0;
+  }
 }
-
 // This function loops for the number of seconds specified by the `secs`
 // parameter and then returns.
 // IMPORTANT: This is not the recommended way to implement 'waiting' in
diff --git a/Week2/prep-exercises/2-experiments/index.js b/Week2/prep-exercises/2-experiments/index.js
@@ -2,45 +2,39 @@
 
 function runExperiment(sampleSize) {
   const valueCounts = [0, 0, 0, 0, 0, 0];
-
-  // TODO
-  // Write a for loop that iterates `sampleSize` times (sampleSize is a number).
-  // In each loop iteration:
-  //
-  // 1. Generate a random integer between 1 and 6 (as if throwing a six-sided die).
-  // 2. Add `1` to the element of the `valueCount` that corresponds to the random
-  //    value from the previous step. Use the first element of `valueCounts`
-  //    for keeping a count how many times the value 1 is thrown, the second
-  //    element for value 2, etc.
+  for (let i = 0; i < sampleSize; i++) {
+    const x = Math.floor(Math.random() * 6);
+    valueCounts[x]++;
+  }
 
   const results = [];
 
-  // TODO
-  // Write a for..of loop for the `valueCounts` array created in the previous
-  // loop. In each loop iteration:
-  // 1. For each possible value of the die (1-6), compute the percentage of how
-  //    many times that value was thrown. Remember that the first value of
-  //    `valueCounts` represent the die value of 1, etc.
-  // 2. Convert the computed percentage to a number string with a precision of
-  //    two decimals, e.g. '14.60'.
-  // 3. Then push that string onto the `results` array.
+  for (const count of valueCounts) {
+    const percent = (count / sampleSize) * 100;
+    results.push(percent.toFixed(2));
+  }
 
   return results;
 }
 
 function main() {
   const sampleSizes = [100, 1000, 1000000];
 
-  // TODO
-  // Write a for..of loop that calls the `runExperiment()` function for each
-  // value of the `sampleSizes` array.
-  // Log the results of each experiment as well as the experiment size to the
-  // console.
-  // The expected output could look like this:
-  //
-  // [ '26.00', '17.00', '10.00', '19.00', '16.00', '12.00' ] 100
-  // [ '14.60', '17.10', '19.30', '15.50', '16.70', '16.80' ] 1000
-  // [ '16.71', '16.68', '16.69', '16.66', '16.67', '16.59' ] 1000000
+  for (const size of sampleSizes) {
+    const experimentResults = runExperiment(size);
+    console.log(experimentResults, size);
+  }
 }
 
+// TODO
+// Write a for..of loop that calls the `runExperiment()` function for each
+// value of the `sampleSizes` array.
+// Log the results of each experiment as well as the experiment size to the
+// console.
+// The expected output could look like this:
+//
+// [ '26.00', '17.00', '10.00', '19.00', '16.00', '12.00' ] 100
+// [ '14.60', '17.10', '19.30', '15.50', '16.70', '16.80' ] 1000
+// [ '16.71', '16.68', '16.69', '16.66', '16.67', '16.59' ] 1000000
+
 main();
