봉우리 수.js

function solution(arr) {
  let answer = 0;
  let n = arr.length;
  let dx = [-1, 0, 1, 0];
  let dy = [0, 1, 0, -1];
  for (let i = 0; i < n; i++) {
    for (let j = 0; j < n; j++) {
      let flag = 1;
      for (let k = 0; k < 4; k++) {
        let nx = i + dx[k];
        let ny = j + dy[k];
        if (nx >= 0 && nx < n && ny >= 0 && ny < n && arr[nx][ny] > arr[i][j]) {
          flag = 0;
          break;
        }
      }
      if (flag) answer++;
    }
  }
  return answer;
}

console.log(
  solution([
    [5, 3, 7, 2, 3],
    [3, 7, 1, 6, 1],
    [7, 2, 5, 3, 4],
    [4, 3, 6, 4, 1],
    [8, 7, 3, 5, 2],
  ])
);