版权声明:如需转载请联系[email protected] https://blog.csdn.net/qq_20633793/article/details/82079919
思路:不是特比容易用语言的描述,用图形描述比较方便,但无奈作图成本太高,直接看代码,也是容易理解的。
class Solution {
public:
int surfaceArea(vector<vector<int>>& grid) {
int cnt=0,n=grid.size(),cnt1=0,cnt2=0;
if(n==0)return 0;
vector<vector<int> > hang=grid,lie=grid;
for(int i=0;i<n;i++){
for(int j=0;j<n;j++){
if(grid[i][j]!=0)cnt++;
if(i!=0)hang[i][j]=abs(grid[i][j]-grid[i-1][j]);
if(j!=0)lie[i][j]=abs(grid[i][j]-grid[i][j-1]);
}
}
for(int i=0;i<n;i++)
for(int j=0;j<n;j++){
cnt1+=hang[i][j];
cnt2+=lie[i][j];
}
for(int i=0;i<n;i++){cnt1+=grid[n-1][i];cnt2+=grid[i][n-1];}
return cnt*2+cnt1+cnt2;
}
};