运行 ID: 3654

Main.cc: In function ‘int main()’:
Main.cc:5:5: error: expected unqualified-id before ‘>>’ token
  int>>n;
     ^~
Main.cc:6:17: error: ‘n’ was not declared in this scope
  for(int i=1;i<=n;i++){
                 ^
Main.cc:7:12: error: expected ‘;’ before ‘<=’ token
   for(int j<=n;j++){
            ^~
Main.cc:7:12: error: expected primary-expression before ‘<=’ token
Main.cc:9:23: error: ‘sum’ was not declared in this scope
    if(i+j==n+1||i==j) sum+=a[i][j];
                       ^~~
Main.cc:12:8: error: ‘sum’ was not declared in this scope
  cout<