/in/foo.cc: In function 'int main()':
/in/foo.cc:4:16: error: 'sum' was not declared in this scope
  long long i = sum = 1;
                ^~~
/in/foo.cc:5:8: error: expected '(' before 'i'
  while i<=100:
        ^
/in/foo.cc:5:14: error: expected ')' before ':' token
  while i<=100:
              ^
/in/foo.cc:5:14: error: expected primary-expression before ':' token
/in/foo.cc:8:2: error: expected ';' before 'cout'
  cout<<sum;
  ^~~~