Recursion Practice Quiz¶

Question 1¶

recursion-quiz1: What would the following code print?:

function mystery(x, y){
  if (x < 1){
    return y;
  }
  else {
    return mystery(x - 1 , y + 1);
  }
}

console.log(mystery(5,10));

Question 2¶

recursion-quiz2: What would the following code print?:

function mystery(n){
  if (n === 0) {
    return 1;
  }
  else {
    return 2 * mystery(n-1);
  }
}

console.log(mystery(6));

Question 3¶

recursion-quiz3: What would the following code print?:

function printInfo(n){
  if (n < 0){
    return n;
  }
  else if (n > LIMIT) {
    return n;
  }
  else {
    console.log(n);
    printInfo(n + 100);
  }
}

let LIMIT = 500;
printInfo(1);

Note: Although each print statement would happen on it’s own line, just separate the lines with a space in your answer. For example, if the lines printed were 42, 58 and 106, you would enter 42 58 106.

Question 4¶

recursion-quiz4: What would the following code print?:

function mystery(n){
  if (n > 100) {
    return n;
  }
  else if (n < 50) {
    return mystery(n * 2);
  }
  else {
    return mystery(n * 3);
  }
}

console.log(mystery(5));

5 x 2 = 10 10 x 2 = 20 20 x 2 = 40 40 x 2 = 80 80 x 3 = 240

Question 5¶

recursion-quiz5: What would the following code print?:

function stringRecursion(str, c) {
  if (c === 0) {
    return str;
  }
  else if (str.slice(0,1) === "c") {
    return stringRecursion(str.slice(1) + "c", c - 1);
  }
  else if (str.slice(0,1) === "o") {
    return stringRecursion(str.slice(1) + "o", c - 2);
  }
  else {
    return stringRecursion(str.slice(1) + "n", c - 1);
  }
}

console.log(stringRecursion("cocoon", 9));

str	c
“cocoon”	9
“ocoonc”	8
“coonco”	6
“ooncoc”	5
“oncoco”	3
“ncocoo”	1
“cocoon”	0

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