运行 ID: 3751

Main.cc: In function ‘int main()’:
Main.cc:5:11: error: expected initializer before ‘++’ token
  int n,sum++;
           ^~
Main.cc:13:15: error: ‘sum’ was not declared in this scope
       a[i][j]=sum;
               ^~~
Main.cc:17:5: error: ‘i’ was not declared in this scope
  if(i%2==0)
     ^
Main.cc:21:12: error: ‘sum’ was not declared in this scope
    a[i][j]=sum;
            ^~~