Submission #1275373

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Source Code Expand

import std.stdio, std.array, std.string, std.conv, std.algorithm;
import std.typecons, std.range, std.random, std.math, std.container;
import std.numeric, std.bigint, core.bitop;

int[] dr = [1, -1, 0, 0];
int[] dc = [0, 0, 1, -1];

void main() {
    auto s = readln.split.map!(to!int);
    auto H = s[0];
    auto W = s[1];
    auto B = H.iota.map!(_ => readln.split.map!(to!int).array).array;

    int ans = 0;
    auto F = new int[](W);
    foreach (_; 0..H*W) {
        bool ate = false;
        foreach (i; 0..W) {
            if (F[i] < H && B[F[i]][i] == 1) {
                foreach (k; 0..4) {
                    int nr = F[i] + dr[k];
                    int nc = i + dc[k];
                    if (nr >= 0 && nr < H && nc >= 0 && nc < W) B[nr][nc] ^= 1;
                }
                ate = true;
                F[i] += 1;
                ans += 1;
                break;
            }
        }
        if (!ate) {
            foreach (i; 0..W) {
                if (F[i] < H) {
                    foreach (k; 0..4) {
                        int nr = F[i] + dr[k];
                        int nc = i + dc[k];
                        if (nr >= 0 && nr < H && nc >= 0 && nc < W) B[nr][nc] ^= 1;
                    }
                    F[i] += 1; break;
                }
            }
        }

    }

    ans.writeln;
}

Submission Info

Judge Result