每日一题---807. 保持城市天际线[力扣][Go]

// 贪心来做
func maxIncreaseKeepingSkyline(grid [][]int) int {
  res := 0
  var LAndR = make([]int, len(grid))
  var FAndA = make([]int, len(grid[0]))
  // 观察左右天际线
  for i, i2 := range grid {
    max := 0
    for _, i3 := range i2 {
      if max < i3 {
        max = i3
      }
    }
    LAndR[i] = max
  }
  // 观察前后天际线
  for i := 0; i < len(grid[0]); i++ {
    max := 0
    for j := 0; j < len(grid); j++ {
      if grid[j][i] > max {
        max = grid[j][i]
      }
    }
    FAndA[i] = max
  }
  // 建筑物高度可以增加的最大总和
  for i, ints := range grid {
    for j, i1 := range ints {
      if LAndR[i] > FAndA[j] {
        res += FAndA[j] - i1
      } else {
        res += LAndR[i] - i1
      }
    }
  }
  return res
}