function marsExploration(s) {
    let actualStr = "SOS";
    let misMatchCount = 0;
    let j = 0;
    let k = 0;
    let emptyArray = [];
    let n = [];

  while (j < s.length) {
    if (s[j] !== actualStr[k]) {
      misMatchCount++;
    }
    j++;
    k++;
    if (k > 2) {
      k = 0;
    }
  }
  return misMatchCount;
}