IslandPerimeter

委曲算一道搜索吧。。

class Solution {
public:
    int islandPerimeter(vector<vector<int>>& grid) {
        int row = grid.size();
        int col = grid[0].size();
        int sum = 0;
        for(int i=0 ;i<row ; i++){
            for(int j=0 ;j<col ; j++){
                if(grid[i][j] == 1){
                    sum += cal(grid,i,j,row,col);
                }
            }
        }
        return sum;
    }
    
    int cal(vector<vector<int>>& grid,int x,int y,int row,int col){
        int count = 0;
        int fx[4][2] = {0,1,0,-1,1,0,-1,0};
        for(int i=0 ;i<4; i++){
            int nx = x + fx[i][0];
            int ny = y + fx[i][1];
            if(nx<0 || nx >=row || ny<0 || ny>=col){
                count ++;
            }
            else if(nx>=0 && nx<row && ny>=0 && ny<col ){
                if(grid[nx][ny] == 0){
                    count ++;
                }
            }
        }
        return count;
    }
};class Solution {
public:
    int islan