foo.cc:1:1: error: expected unqualified-id before 'for'
 for(int k=1;k<i;k++)
 ^~~
foo.cc:1:13: error: 'k' does not name a type
 for(int k=1;k<i;k++)
             ^
foo.cc:1:17: error: 'k' does not name a type
 for(int k=1;k<i;k++)
                 ^
foo.cc:5:3: error: expected unqualified-id before 'for'
   for(int j=1;j<=(n-i)*2+1;j++)
   ^~~
foo.cc:5:15: error: 'j' does not name a type
   for(int j=1;j<=(n-i)*2+1;j++)
               ^
foo.cc:5:28: error: 'j' does not name a type
   for(int j=1;j<=(n-i)*2+1;j++)
                            ^
foo.cc:9:3: error: 'cout' does not name a type
   cout<<endl;
   ^~~~

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