foo.cc:7:11: warning: integer constant is too large for its type
     int k[100000000000000000000];
           ^~~~~~~~~~~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:7:32: error: size of array 'k' is too large
     int k[100000000000000000000];
                                ^
foo.cc:8:5: error: 'k' was not declared in this scope
     k[1]=0;
     ^

自豪的采用 HydroJudge 进行评测(github.com/hydro-dev/HydroJudge)