Warm Up-1

SleepIn

public boolean sleepIn(boolean weekday, boolean vacation) {
  if (!weekday || vacation) return true;
  return false;
}

monkeyTrouble

public boolean monkeyTrouble(boolean aSmile, boolean bSmile) {
  if (aSmile == bSmile) return true;
  return false;
}

sumDouble

public int sumDouble(int a, int b) {
  if (a == b) return 2*(a+b);
  return a+b;
}

diff21

public int diff21(int n) {
  if (n > 21) return 2*(n-21);
  return Math.abs(n - 21);
}

parrotTrouble

public boolean parrotTrouble(boolean talking, int hour) {
  if ((hour > 20 || hour < 7) && talking) return true;
  return false;
}

makes

public boolean makes10(int a, int b) {
  if (a == 10 || b == 10) return true;
  if (a + b == 10) return true;
  return false;
}

public boolean makes10(int a, int b) {
  return (a == 10 || b == 10 || a+b == 10);
}

nearHundred

public boolean nearHundred(int n) {
  if (Math.abs(100 - n) <= 10 || Math.abs(200 - n) <= 10) return true;
  return false;
}

public boolean nearHundred(int n) {
  return ((Math.abs(100 - n) <= 10) ||
    (Math.abs(200 - n) <= 10));
}

posNeg

public boolean posNeg(int a, int b, boolean negative) {
  if (!negative && a*b < 0) return true;
  if (negative && a < 0 && b < 0) return true;
  return false;
}

notString

public String notString(String str) {
  if (str.length() >= 3 && str.substring(0, 3).equals("not")) return str;
  return "not " + str;
}

missingChar

public String missingChar(String str, int n) {
  return str.substring(0,n ) + str.substring(n+1, str.length());
}

frontBack

public String frontBack(String str) {
      if(str.length() > 1){
          String back = str.substring(str.length() - 1);
          String front = str.substring(0, 1);
          String mid = str.substring(1, str.length() -1);
          return back + mid + front;
      }
      return str;
  }

front3

public String front3(String str) {
      if (str.length() > 2) {
          String str1 = str.substring(0, 3);
          return str1 + str1 + str1;
      }
      return str + str + str;
  }

backAround

public String backAround(String str) {
       char a = str.charAt(str.length() - 1);
       return a + str + a;
   }

or35

public boolean or35(int n) {
       return (n % 3 == 0 || n % 5 == 0);
   }

front22

public String front22(String str) {
       if (str.length() > 1) {
           String front = str.substring(0, 2);
           return front + str + front;
       }
       return str + str + str;
   }

startHi

public boolean startHi(String str) {
     if (str.length() > 1) {
         return str.substring(0, 2).equals("hi");
     }
     return false;
 }

icyHot

public boolean icyHot(int temp1, int temp2) {
       return (temp1 < 0 && temp2 > 100) || (temp1 > 100 && temp2 < 0);
   }

in1020

public boolean in1020(int a, int b) {
       return (a >= 10 && a <= 20) || (b >= 10 && b <= 20);
   }

hasTeen

public boolean hasTeen(int a, int b, int c) {
      return (a >= 13 && a <= 19) || (b >= 13 && b <= 19) || (c >= 13 && c <= 19);
  }

loneTeen

public boolean loneTeen(int a, int b) {
        return ((a >= 13 && a <= 19) && (b < 13 || b > 19)) || ((b >= 13 && b <= 19) && (a < 13 || a > 19));
    }

delDel

public String delDel(String str) {
       int foundDel = str.indexOf("del");
       if (foundDel == 1) {
           return str.substring(0, foundDel) + str.substring(foundDel + 3);
       }
       return str;
   }

mixStart

public boolean mixStart(String str) {
       if (str.length() > 2) {
           return str.substring(1, 3).equals("ix");
       }
       return false;
   }

startOz

public String startOz(String str) {
        if ((str.length() > 1) && (str.substring(0, 2).equals("oz"))) {
            return str.substring(0, 2);
        } else if ((str.length() > 0) && (str.substring(0, 1).equals("o"))) {
            return str.substring(0, 1);
        } else if ((str.length() > 1) && (str.substring(1, 2).equals("z"))) {
            return str.substring(1, 2);
        } else {
            return "";
        }
    }

intMax

public int intMax(int a, int b, int c) {
       int max = 0;
       if (a >= max || a < 0) {
           max = a;
       }
       if (b >= max) {
           max = b;
       }
       if (c > max) {
           max = c;
       }
       return max;
   }

close10

public int close10(int a, int b) {
       int diffa = a - 10;
       diffa = Math.abs(diffa);
       int diffb = b - 10;
       diffb = Math.abs(diffb);
       if (diffa < diffb) {
           return a;
       } else if (diffa > diffb) {
           return b;
       } else {
           return 0;
       }
   }

in3050

public boolean in3050(int a, int b) {
        if ((a >= 30 && a <= 40) && (b >= 30 && b <= 40)) {
            return true;
        } else if ((a >= 40 && a <= 50) && (b >= 40 && b <= 50)) {
            return true;
        }
        return false;
    }

max1020

public int max1020(int a, int b) {
       if ((a >= 10 && a <= 20) && (b >= 10 && b <= 20)) {
           if (a > b) {
               return a;
           } else {
               return b;
           }
       }
       if (a >= 10 && a <= 20) {
           return a;
       } else if (b >= 10 && b <= 20) {
           return b;
       }
       return 0;
   }

stringE

public boolean stringE(String str) {
        int count = 0;
        for (int i = 0; i < str.length(); i++) {
            if (str.indexOf("e", i) == i) {
                count++;
            }
        }
        if (count <= 3 && count >= 1) {
            return true;
        }
        return false;
    }

lastDigit

public boolean lastDigit(int a, int b) {
       int modA = a % 10;
       int modB = b % 10;
       if (modA == modB && a >= 10 && b >= 10) {
           return true;
       } else if ((a < 10 || b < 10) && (modA == b || modB == a)) {
           return true;
       }
       return false;
   }

endUp

public String endUp(String str) {
       if (str.length() <= 3) {
           return str.toUpperCase();
       } else if (str.length() > 3) {
           String last3 = str.substring(str.length() - 3).toUpperCase();
           return str.substring(0, str.length() - 3) + last3;
       }
       return str;
   }

everyNth

public String everyNth(String str, int n) {
       String a = null;
       int count = 0;
       for (int i = 0; i < str.length(); i++) {
           if (i * n < str.length()) {
               count++;
           }
       }
       char strChars[] = new char[count];
       for (int i = 0; i < str.length(); i++) {
           if (i * n < str.length()) {
               strChars[i] = str.charAt(i * n);
           }
       }
       a = new String(strChars);
       return a;
   }