Submission #2486303

---

Source Code Expand

package main

import (
  "bufio"
  "fmt"
  "os"
  "strconv"
)

var sc = bufio.NewScanner(os.Stdin)

func nextInt() int {
    sc.Scan()
    i, _ := strconv.Atoi(sc.Text())
    return i
}

func max(a int, b int) int {
  if a > b {
    return a
  } else {
    return b
  }
}

func main() {
  sc.Split(bufio.ScanWords)
  h := nextInt()
  w := nextInt()
  squares := make([][]int, h+1)
  for i := range squares {
    squares[i] = make([]int, w+1)
  }
  for i := 1; i <= h; i++ {
    for j:= 1; j <= w; j++ {
      c := nextInt()
      squares[i][j] += squares[i][j-1]
      if (i ^ j) & 1 == 0 {
        squares[i][j] += c
      } else {
        squares[i][j] -= c
      }
    }
  }
  for j := 1; j <= w; j++ {
    for i := 2; i <= h; i++ {
      squares[i][j] += squares[i-1][j]
    }
  }
  max_ := 0
  for i := 1; i <= h; i++ {
    for j := 1; j <= w; j++ {
      for ii := i; ii <= h; ii++ {
        for jj := j; jj <= w; jj++ {
          //   h 0 □ □ □ □ □
          //  ii 0 □ ■ ■ ■ □
          //   i 0 □ ■ ■ ■ □
          //     0 □ □ □ □ □
          //   0 0 0 0 0 0 0
          //     0   j   jj w
          if (squares[ii][jj] - squares[i-1][jj] - squares[ii][j-1] + squares[i-1][j-1] == 0) {
            max_ = max(max_, (ii-i+1) * (jj-j+1))
          }
        }
      }
    }
  }
  fmt.Println(max_)
}

Submission Info

Judge Result