这个题没必要这么麻烦吧，边读边加就行了
```cpp
#include<iostream>
using namespace std;
int a[105][105];
int main(){
int m,n;
long long sum=0;
cin>>m>>n;
for(int i=0;i<m;i++){
for(int j=0;j<n;j++){
cin>>a[i][j];
if(i==0||j==0||i==m-1||j==n-1){
sum+=a[i][j];
}
}
}
cout<<sum<<endl;
return 0;
}
```
by chenlh0711 @ 2024-02-21 19:52:59
```cpp
#include<iostream>
using namespace std;
int main(){
int n,m,a[101][101],sum=0;
cin >> m >> n;
for(int i=1;i<=m;i++){
for(int j=1;j<=n;j++){
cin >> a[i][j];
if(i==1||j==1||i==m||j==n){
sum+=a[i][j];
}
}
}
cout << sum;
return 0;
}
```
by huang_yi_hang2014 @ 2024-02-21 20:23:15