6-1.linq

<Query Kind="Program" />

void Main()
{
    string inputString = @"turn off 660,55 through 986,197;turn off 341,304 through 638,850;turn off 199,133 through 461,193;toggle 322,558 through 977,958;toggle 537,781 through 687,941;turn on 226,196 through 599,390;turn on 240,129 through 703,297;turn on 317,329 through 451,798;turn on 957,736 through 977,890;turn on 263,530 through 559,664;turn on 158,270 through 243,802;toggle 223,39 through 454,511;toggle 544,218 through 979,872;turn on 313,306 through 363,621;toggle 173,401 through 496,407;toggle 333,60 through 748,159;turn off 87,577 through 484,608;turn on 809,648 through 826,999;toggle 352,432 through 628,550;turn off 197,408 through 579,569;turn off 1,629 through 802,633;turn off 61,44 through 567,111;toggle 880,25 through 903,973;turn on 347,123 through 864,746;toggle 728,877 through 996,975;turn on 121,895 through 349,906;turn on 888,547 through 931,628;toggle 398,782 through 834,882;turn on 966,850 through 989,953;turn off 891,543 through 914,991;toggle 908,77 through 916,117;turn on 576,900 through 943,934;turn off 580,170 through 963,206;turn on 184,638 through 192,944;toggle 940,147 through 978,730;turn off 854,56 through 965,591;toggle 717,172 through 947,995;toggle 426,987 through 705,998;turn on 987,157 through 992,278;toggle 995,774 through 997,784;turn off 796,96 through 845,182;turn off 451,87 through 711,655;turn off 380,93 through 968,676;turn on 263,468 through 343,534;turn on 917,936 through 928,959;toggle 478,7 through 573,148;turn off 428,339 through 603,624;turn off 400,880 through 914,953;toggle 679,428 through 752,779;turn off 697,981 through 709,986;toggle 482,566 through 505,725;turn off 956,368 through 993,516;toggle 735,823 through 783,883;turn off 48,487 through 892,496;turn off 116,680 through 564,819;turn on 633,865 through 729,930;turn off 314,618 through 571,922;toggle 138,166 through 936,266;turn on 444,732 through 664,960;turn off 109,337 through 972,497;turn off 51,432 through 77,996;turn off 259,297 through 366,744;toggle 801,130 through 917,544;toggle 767,982 through 847,996;turn on 216,507 through 863,885;turn off 61,441 through 465,731;turn on 849,970 through 944,987;toggle 845,76 through 852,951;toggle 732,615 through 851,936;toggle 251,128 through 454,778;turn on 324,429 through 352,539;toggle 52,450 through 932,863;turn off 449,379 through 789,490;turn on 317,319 through 936,449;toggle 887,670 through 957,838;toggle 671,613 through 856,664;turn off 186,648 through 985,991;turn off 471,689 through 731,717;toggle 91,331 through 750,758;toggle 201,73 through 956,524;toggle 82,614 through 520,686;toggle 84,287 through 467,734;turn off 132,367 through 208,838;toggle 558,684 through 663,920;turn on 237,952 through 265,997;turn on 694,713 through 714,754;turn on 632,523 through 862,827;turn on 918,780 through 948,916;turn on 349,586 through 663,976;toggle 231,29 through 257,589;toggle 886,428 through 902,993;turn on 106,353 through 236,374;turn on 734,577 through 759,684;turn off 347,843 through 696,912;turn on 286,699 through 964,883;turn on 605,875 through 960,987;turn off 328,286 through 869,461;turn off 472,569 through 980,848;toggle 673,573 through 702,884;turn off 398,284 through 738,332;turn on 158,50 through 284,411;turn off 390,284 through 585,663;turn on 156,579 through 646,581;turn on 875,493 through 989,980;toggle 486,391 through 924,539;turn on 236,722 through 272,964;toggle 228,282 through 470,581;toggle 584,389 through 750,761;turn off 899,516 through 900,925;turn on 105,229 through 822,846;turn off 253,77 through 371,877;turn on 826,987 through 906,992;turn off 13,152 through 615,931;turn on 835,320 through 942,399;turn on 463,504 through 536,720;toggle 746,942 through 786,998;turn off 867,333 through 965,403;turn on 591,477 through 743,692;turn off 403,437 through 508,908;turn on 26,723 through 368,814;turn on 409,485 through 799,809;turn on 115,630 through 704,705;turn off 228,183 through 317,220;toggle 300,649 through 382,842;turn off 495,365 through 745,562;turn on 698,346 through 744,873;turn on 822,932 through 951,934;toggle 805,30 through 925,421;toggle 441,152 through 653,274;toggle 160,81 through 257,587;turn off 350,781 through 532,917;toggle 40,583 through 348,636;turn on 280,306 through 483,395;toggle 392,936 through 880,955;toggle 496,591 through 851,934;turn off 780,887 through 946,994;turn off 205,735 through 281,863;toggle 100,876 through 937,915;turn on 392,393 through 702,878;turn on 956,374 through 976,636;toggle 478,262 through 894,775;turn off 279,65 through 451,677;turn on 397,541 through 809,847;turn on 444,291 through 451,586;toggle 721,408 through 861,598;turn on 275,365 through 609,382;turn on 736,24 through 839,72;turn off 86,492 through 582,712;turn on 676,676 through 709,703;turn off 105,710 through 374,817;toggle 328,748 through 845,757;toggle 335,79 through 394,326;toggle 193,157 through 633,885;turn on 227,48 through 769,743;toggle 148,333 through 614,568;toggle 22,30 through 436,263;toggle 547,447 through 688,969;toggle 576,621 through 987,740;turn on 711,334 through 799,515;turn on 541,448 through 654,951;toggle 792,199 through 798,990;turn on 89,956 through 609,960;toggle 724,433 through 929,630;toggle 144,895 through 201,916;toggle 226,730 through 632,871;turn off 760,819 through 828,974;toggle 887,180 through 940,310;toggle 222,327 through 805,590;turn off 630,824 through 885,963;turn on 940,740 through 954,946;turn on 193,373 through 779,515;toggle 304,955 through 469,975;turn off 405,480 through 546,960;turn on 662,123 through 690,669;turn off 615,238 through 750,714;turn on 423,220 through 930,353;turn on 329,769 through 358,970;toggle 590,151 through 704,722;turn off 884,539 through 894,671;toggle 449,241 through 984,549;toggle 449,260 through 496,464;turn off 306,448 through 602,924;turn on 286,805 through 555,901;toggle 722,177 through 922,298;toggle 491,554 through 723,753;turn on 80,849 through 174,996;turn off 296,561 through 530,856;toggle 653,10 through 972,284;toggle 529,236 through 672,614;toggle 791,598 through 989,695;turn on 19,45 through 575,757;toggle 111,55 through 880,871;turn off 197,897 through 943,982;turn on 912,336 through 977,605;toggle 101,221 through 537,450;turn on 101,104 through 969,447;toggle 71,527 through 587,717;toggle 336,445 through 593,889;toggle 214,179 through 575,699;turn on 86,313 through 96,674;toggle 566,427 through 906,888;turn off 641,597 through 850,845;turn on 606,524 through 883,704;turn on 835,775 through 867,887;toggle 547,301 through 897,515;toggle 289,930 through 413,979;turn on 361,122 through 457,226;turn on 162,187 through 374,746;turn on 348,461 through 454,675;turn off 966,532 through 985,537;turn on 172,354 through 630,606;turn off 501,880 through 680,993;turn off 8,70 through 566,592;toggle 433,73 through 690,651;toggle 840,798 through 902,971;toggle 822,204 through 893,760;turn off 453,496 through 649,795;turn off 969,549 through 990,942;turn off 789,28 through 930,267;toggle 880,98 through 932,434;toggle 568,674 through 669,753;turn on 686,228 through 903,271;turn on 263,995 through 478,999;toggle 534,675 through 687,955;turn off 342,434 through 592,986;toggle 404,768 through 677,867;toggle 126,723 through 978,987;toggle 749,675 through 978,959;turn off 445,330 through 446,885;turn off 463,205 through 924,815;turn off 417,430 through 915,472;turn on 544,990 through 912,999;turn off 201,255 through 834,789;turn off 261,142 through 537,862;turn off 562,934 through 832,984;turn off 459,978 through 691,980;turn off 73,911 through 971,972;turn on 560,448 through 723,810;turn on 204,630 through 217,854;turn off 91,259 through 611,607;turn on 877,32 through 978,815;turn off 950,438 through 974,746;toggle 426,30 through 609,917;toggle 696,37 through 859,201;toggle 242,417 through 682,572;turn off 388,401 through 979,528;turn off 79,345 through 848,685;turn off 98,91 through 800,434;toggle 650,700 through 972,843;turn off 530,450 through 538,926;turn on 428,559 through 962,909;turn on 78,138 through 92,940;toggle 194,117 through 867,157;toggle 785,355 through 860,617;turn off 379,441 through 935,708;turn off 605,133 through 644,911;toggle 10,963 through 484,975;turn off 359,988 through 525,991;turn off 509,138 through 787,411;toggle 556,467 through 562,773;turn on 119,486 through 246,900;turn on 445,561 through 794,673;turn off 598,681 through 978,921;turn off 974,230 through 995,641;turn off 760,75 through 800,275;toggle 441,215 through 528,680;turn off 701,636 through 928,877;turn on 165,753 through 202,780;toggle 501,412 through 998,516;toggle 161,105 through 657,395;turn on 113,340 through 472,972;toggle 384,994 through 663,999;turn on 969,994 through 983,997;turn on 519,600 through 750,615;turn off 363,899 through 948,935;turn on 271,845 through 454,882;turn off 376,528 through 779,640;toggle 767,98 through 854,853;toggle 107,322 through 378,688;turn off 235,899 through 818,932;turn on 445,611 through 532,705;toggle 629,387 through 814,577;toggle 112,414 through 387,421;toggle 319,184 through 382,203;turn on 627,796 through 973,940;toggle 602,45 through 763,151;turn off 441,375 through 974,545;toggle 871,952 through 989,998;turn on 717,272 through 850,817;toggle 475,711 through 921,882;toggle 66,191 through 757,481;turn off 50,197 through 733,656;toggle 83,575 through 915,728;turn on 777,812 through 837,912;turn on 20,984 through 571,994;turn off 446,432 through 458,648;turn on 715,871 through 722,890;toggle 424,675 through 740,862;toggle 580,592 through 671,900;toggle 296,687 through 906,775";
    int gridSize = 1000;
    int[,] grid = new int[gridSize,gridSize];
    foreach (var input in inputString.Split(';'))
    {
        string[] numbers = Regex.Split(input, @"\D+");
        int x1 = int.Parse(numbers[1]);
        int y1 = int.Parse(numbers[2]);
        int x2 = int.Parse(numbers[3]);
        int y2 = int.Parse(numbers[4]);

        if (input.StartsWith("turn on"))
        {
            for (int i = x1; i <= x2; i++)
            {
                for (int j = y1; j <= y2; j++)
                {
                    grid[i, j] = 1;
                }
            }
        }
        else if (input.StartsWith("turn off"))
        {
            for (int i = x1; i <= x2; i++)
            {
                for (int j = y1; j <= y2; j++)
                {
                    grid[i, j] = 0;
                }
            }
        }
        else if (input.StartsWith("toggle"))
        {
            for (int i = x1; i <= x2; i++)
            {
                for (int j = y1; j <= y2; j++)
                {
                    if (grid[i, j] == 0) grid[i, j] = 1;
                    else grid[i, j] = 0;
                }
            }
        }
    }
    
    int count = 0;
   foreach (var c in grid)
   {
       if (c == 1) count++;
   }
   count.Dump();
}