using System; class Program { static void Main() { double n; //If the current door number is the perfect square of an integer, say it is open, else say it is closed. for (int d = 1; d <= 100; d++) Console.WriteLine("Door #{0}: {1}", d, (n = Math.Sqrt(d)) == (int)n ? "Open" : "Closed"); } }
Standard input is empty
Door #1: Open Door #2: Closed Door #3: Closed Door #4: Open Door #5: Closed Door #6: Closed Door #7: Closed Door #8: Closed Door #9: Open Door #10: Closed Door #11: Closed Door #12: Closed Door #13: Closed Door #14: Closed Door #15: Closed Door #16: Open Door #17: Closed Door #18: Closed Door #19: Closed Door #20: Closed Door #21: Closed Door #22: Closed Door #23: Closed Door #24: Closed Door #25: Open Door #26: Closed Door #27: Closed Door #28: Closed Door #29: Closed Door #30: Closed Door #31: Closed Door #32: Closed Door #33: Closed Door #34: Closed Door #35: Closed Door #36: Open Door #37: Closed Door #38: Closed Door #39: Closed Door #40: Closed Door #41: Closed Door #42: Closed Door #43: Closed Door #44: Closed Door #45: Closed Door #46: Closed Door #47: Closed Door #48: Closed Door #49: Open Door #50: Closed Door #51: Closed Door #52: Closed Door #53: Closed Door #54: Closed Door #55: Closed Door #56: Closed Door #57: Closed Door #58: Closed Door #59: Closed Door #60: Closed Door #61: Closed Door #62: Closed Door #63: Closed Door #64: Open Door #65: Closed Door #66: Closed Door #67: Closed Door #68: Closed Door #69: Closed Door #70: Closed Door #71: Closed Door #72: Closed Door #73: Closed Door #74: Closed Door #75: Closed Door #76: Closed Door #77: Closed Door #78: Closed Door #79: Closed Door #80: Closed Door #81: Open Door #82: Closed Door #83: Closed Door #84: Closed Door #85: Closed Door #86: Closed Door #87: Closed Door #88: Closed Door #89: Closed Door #90: Closed Door #91: Closed Door #92: Closed Door #93: Closed Door #94: Closed Door #95: Closed Door #96: Closed Door #97: Closed Door #98: Closed Door #99: Closed Door #100: Open