mysteryorganism.js

// Returns a random DNA base
const returnRandBase = () => {
  const dnaBases = ['A', 'T', 'C', 'G']
  return dnaBases[Math.floor(Math.random() * 4)] 
}

// Returns a random single strand of DNA containing 15 bases
const mockUpStrand = () => {
  const newStrand = []
  for (let i = 0; i < 15; i++) {
    newStrand.push(returnRandBase())
  }
  return newStrand
}

const pAequorFactory = (num, arr) => {
  return {
    specimenNum: num,
    dna: arr,
    mutate() {
      const randNum = Math.floor(Math.random() * 15);
      const dnaBases = ['A', 'T', 'C', 'G']
      const randBase = returnRandBase();
        if (arr[randNum] !== randBase) {
          arr[randNum] = randBase;
        } else {
          arr[randNum] = dnaBases[Math.floor(Math.random() * 4) - 1];
        }
    
      const newArr  = arr.splice(randNum, 1, arr[randNum]);
      return newArr;
      this.dna = newArr;
    },

    compareDNA(pAequor) {
      let numSame = 0;
      for (let i=0; i<arr.length; i++) {
        if (this.dna[i] === pAequor.dna[i]) {
          numSame++;
        } else {
          numSame = numSame;
        }
      }
      const percent = (numSame / 15) * 100;
      return `specimen #${this.specimenNum} and specimen #${pAequor.specimenNum} have ${percent.toFixed(2)}% DNA in common.`;
    },

    willLikelySurvive() {
      let corg = 0;
      for (let i=0; i<arr.length; i++) {
        if (this.dna[i] === 'C') {
          corg++;
        } else if (this.dna[i] === 'G') {
          corg++;
        }
      }
      const corgPerc = (corg / 15) * 100;
        if (corgPerc >= 60) {
          return true;
        } else {
          return false;
        }
      }  
    } 
  }

let aequorSet = [];
let setDone = false;
for (let i=1; setDone === false; i++) {
  let aequorObj = pAequorFactory(i, mockUpStrand());
  if (aequorObj.willLikelySurvive() === true) {
    aequorSet.push(aequorObj);
  }
  if (aequorSet.length === 30) {
    setDone = true;
  } else {
    setDone = false;
  }
} 

console.log(aequorSet);