lights = Hash.new {|h,k| h[k] = 0 } instructions = { "turn on" => ->(intensity) { intensity + 1 }, "turn off" => ->(intensity) { intensity.zero? ? 0 : intensity - 1 }, "toggle" => ->(intensity) { intensity + 2 } } regex = /(turn on|turn off|toggle) (\d+),(\d+) through (\d+),(\d+)/ DATA.read.scan(regex).each do |instruction, x1,y1, x2,y2| min_x,max_x = [x1,x2].map(&:to_i).sort min_y,max_y = [y1,y2].map(&:to_i).sort instruction = instructions[instruction] (min_x..max_x).each do |x| (min_y..max_y).each do |y| lights[[x,y]] = instruction[lights[[x,y]]] end end end puts lights.values.inject(&:+) __END__ turn on 887,9 through 959,629 turn on 454,398 through 844,448 turn off 539,243 through 559,965 turn off 370,819 through 676,868 turn off 145,40 through 370,997 turn off 301,3 through 808,453 turn on 351,678 through 951,908 toggle 720,196 through 897,994 toggle 831,394 through 904,860 toggle 753,664 through 970,926 turn off 150,300 through 213,740 turn on 141,242 through 932,871 toggle 294,259 through 474,326 toggle 678,333 through 752,957 toggle 393,804 through 510,976 turn off 6,964 through 411,976 turn off 33,572 through 978,590 turn on 579,693 through 650,978 turn on 150,20 through 652,719 turn off 782,143 through 808,802 turn off 240,377 through 761,468 turn off 899,828 through 958,967 turn on 613,565 through 952,659 turn on 295,36 through 964,978 toggle 846,296 through 969,528 turn off 211,254 through 529,491 turn off 231,594 through 406,794 turn off 169,791 through 758,942 turn on 955,440 through 980,477 toggle 944,498 through 995,928 turn on 519,391 through 605,718 toggle 521,303 through 617,366 turn off 524,349 through 694,791 toggle 391,87 through 499,792 toggle 562,527 through 668,935 turn off 68,358 through 857,453 toggle 815,811 through 889,828 turn off 666,61 through 768,87 turn on 27,501 through 921,952 turn on 953,102 through 983,471 turn on 277,552 through 451,723 turn off 64,253 through 655,960 turn on 47,485 through 734,977 turn off 59,119 through 699,734 toggle 407,898 through 493,955 toggle 912,966 through 949,991 turn on 479,990 through 895,990 toggle 390,589 through 869,766 toggle 593,903 through 926,943 toggle 358,439 through 870,528 turn off 649,410 through 652,875 turn on 629,834 through 712,895 toggle 254,555 through 770,901 toggle 641,832 through 947,850 turn on 268,448 through 743,777 turn off 512,123 through 625,874 turn off 498,262 through 930,811 turn off 835,158 through 886,242 toggle 546,310 through 607,773 turn on 501,505 through 896,909 turn off 666,796 through 817,924 toggle 987,789 through 993,809 toggle 745,8 through 860,693 toggle 181,983 through 731,988 turn on 826,174 through 924,883 turn on 239,228 through 843,993 turn on 205,613 through 891,667 toggle 867,873 through 984,896 turn on 628,251 through 677,681 toggle 276,956 through 631,964 turn on 78,358 through 974,713 turn on 521,360 through 773,597 turn off 963,52 through 979,502 turn on 117,151 through 934,622 toggle 237,91 through 528,164 turn on 944,269 through 975,453 toggle 979,460 through 988,964 turn off 440,254 through 681,507 toggle 347,100 through 896,785 turn off 329,592 through 369,985 turn on 931,960 through 979,985 toggle 703,3 through 776,36 toggle 798,120 through 908,550 turn off 186,605 through 914,709 turn off 921,725 through 979,956 toggle 167,34 through 735,249 turn on 726,781 through 987,936 toggle 720,336 through 847,756 turn on 171,630 through 656,769 turn off 417,276 through 751,500 toggle 559,485 through 584,534 turn on 568,629 through 690,873 toggle 248,712 through 277,988 toggle 345,594 through 812,723 turn off 800,108 through 834,618 turn off 967,439 through 986,869 turn on 842,209 through 955,529 turn on 132,653 through 357,696 turn on 817,38 through 973,662 turn off 569,816 through 721,861 turn on 568,429 through 945,724 turn on 77,458 through 844,685 turn off 138,78 through 498,851 turn on 136,21 through 252,986 turn off 2,460 through 863,472 turn on 172,81 through 839,332 turn on 123,216 through 703,384 turn off 879,644 through 944,887 toggle 227,491 through 504,793 toggle 580,418 through 741,479 toggle 65,276 through 414,299 toggle 482,486 through 838,931 turn off 557,768 through 950,927 turn off 615,617 through 955,864 turn on 859,886 through 923,919 turn on 391,330 through 499,971 toggle 521,835 through 613,847 turn on 822,787 through 989,847 turn on 192,142 through 357,846 turn off 564,945 through 985,945 turn off 479,361 through 703,799 toggle 56,481 through 489,978 turn off 632,991 through 774,998 toggle 723,526 through 945,792 turn on 344,149 through 441,640 toggle 568,927 through 624,952 turn on 621,784 through 970,788 toggle 665,783 through 795,981 toggle 386,610 through 817,730 toggle 440,399 through 734,417 toggle 939,201 through 978,803 turn off 395,883 through 554,929 turn on 340,309 through 637,561 turn off 875,147 through 946,481 turn off 945,837 through 957,922 turn off 429,982 through 691,991 toggle 227,137 through 439,822 toggle 4,848 through 7,932 turn off 545,146 through 756,943 turn on 763,863 through 937,994 turn on 232,94 through 404,502 turn off 742,254 through 930,512 turn on 91,931 through 101,942 toggle 585,106 through 651,425 turn on 506,700 through 567,960 turn off 548,44 through 718,352 turn off 194,827 through 673,859 turn off 6,645 through 509,764 turn off 13,230 through 821,361 turn on 734,629 through 919,631 toggle 788,552 through 957,972 toggle 244,747 through 849,773 turn off 162,553 through 276,887 turn off 569,577 through 587,604 turn off 799,482 through 854,956 turn on 744,535 through 909,802 toggle 330,641 through 396,986 turn off 927,458 through 966,564 toggle 984,486 through 986,913 toggle 519,682 through 632,708 turn on 984,977 through 989,986 toggle 766,423 through 934,495 turn on 17,509 through 947,718 turn on 413,783 through 631,903 turn on 482,370 through 493,688 turn on 433,859 through 628,938 turn off 769,549 through 945,810 turn on 178,853 through 539,941 turn off 203,251 through 692,433 turn off 525,638 through 955,794 turn on 169,70 through 764,939 toggle 59,352 through 896,404 toggle 143,245 through 707,320 turn off 103,35 through 160,949 toggle 496,24 through 669,507 turn off 581,847 through 847,903 turn on 689,153 through 733,562 turn on 821,487 through 839,699 turn on 837,627 through 978,723 toggle 96,748 through 973,753 toggle 99,818 through 609,995 turn on 731,193 through 756,509 turn off 622,55 through 813,365 turn on 456,490 through 576,548 turn on 48,421 through 163,674 turn off 853,861 through 924,964 turn off 59,963 through 556,987 turn on 458,710 through 688,847 toggle 12,484 through 878,562 turn off 241,964 through 799,983 turn off 434,299 through 845,772 toggle 896,725 through 956,847 turn on 740,289 through 784,345 turn off 395,840 through 822,845 turn on 955,224 through 996,953 turn off 710,186 through 957,722 turn off 485,949 through 869,985 turn on 848,209 through 975,376 toggle 221,241 through 906,384 turn on 588,49 through 927,496 turn on 273,332 through 735,725 turn on 505,962 through 895,962 toggle 820,112 through 923,143 turn on 919,792 through 978,982 toggle 489,461 through 910,737 turn off 202,642 through 638,940 turn off 708,953 through 970,960 toggle 437,291 through 546,381 turn on 409,358 through 837,479 turn off 756,279 through 870,943 turn off 154,657 through 375,703 turn off 524,622 through 995,779 toggle 514,221 through 651,850 toggle 808,464 through 886,646 toggle 483,537 through 739,840 toggle 654,769 through 831,825 turn off 326,37 through 631,69 turn off 590,570 through 926,656 turn off 881,913 through 911,998 turn on 996,102 through 998,616 turn off 677,503 through 828,563 turn on 860,251 through 877,441 turn off 964,100 through 982,377 toggle 888,403 through 961,597 turn off 632,240 through 938,968 toggle 731,176 through 932,413 turn on 5,498 through 203,835 turn on 819,352 through 929,855 toggle 393,813 through 832,816 toggle 725,689 through 967,888 turn on 968,950 through 969,983 turn off 152,628 through 582,896 turn off 165,844 through 459,935 turn off 882,741 through 974,786 turn off 283,179 through 731,899 toggle 197,366 through 682,445 turn on 106,309 through 120,813 toggle 950,387 through 967,782 turn off 274,603 through 383,759 turn off 155,665 through 284,787 toggle 551,871 through 860,962 turn off 30,826 through 598,892 toggle 76,552 through 977,888 turn on 938,180 through 994,997 toggle 62,381 through 993,656 toggle 625,861 through 921,941 turn on 685,311 through 872,521 turn on 124,934 through 530,962 turn on 606,379 through 961,867 turn off 792,735 through 946,783 turn on 417,480 through 860,598 toggle 178,91 through 481,887 turn off 23,935 through 833,962 toggle 317,14 through 793,425 turn on 986,89 through 999,613 turn off 359,201 through 560,554 turn off 729,494 through 942,626 turn on 204,143 through 876,610 toggle 474,97 through 636,542 turn off 902,924 through 976,973 turn off 389,442 through 824,638 turn off 622,863 through 798,863 turn on 840,622 through 978,920 toggle 567,374 through 925,439 turn off 643,319 through 935,662 toggle 185,42 through 294,810 turn on 47,124 through 598,880 toggle 828,303 through 979,770 turn off 174,272 through 280,311 turn off 540,50 through 880,212 turn on 141,994 through 221,998 turn on 476,695 through 483,901 turn on 960,216 through 972,502 toggle 752,335 through 957,733 turn off 419,713 through 537,998 toggle 772,846 through 994,888 turn on 881,159 through 902,312 turn off 537,651 through 641,816 toggle 561,947 through 638,965 turn on 368,458 through 437,612 turn on 290,149 through 705,919 turn on 711,918 through 974,945 toggle 916,242 through 926,786 toggle 522,272 through 773,314 turn on 432,897 through 440,954 turn off 132,169 through 775,380 toggle 52,205 through 693,747 toggle 926,309 through 976,669 turn off 838,342 through 938,444 turn on 144,431 through 260,951 toggle 780,318 through 975,495 turn off 185,412 through 796,541 turn on 879,548 through 892,860 turn on 294,132 through 460,338 turn on 823,500 through 899,529 turn off 225,603 through 483,920 toggle 717,493 through 930,875 toggle 534,948 through 599,968 turn on 522,730 through 968,950 turn off 102,229 through 674,529