foo.cpp: In function 'int main()':
foo.cpp:8:30: error: 'k' was not declared in this scope
foo.cpp:8:33: error: 'g' was not declared in this scope
foo.cpp:7:13: warning: unused variable 'ans' [-Wunused-variable]
foo.cpp:7:19: warning: unused variable 'i' [-Wunused-variable]
foo.cpp:7:21: warning: unused variable 'j' [-Wunused-variable]