foo.cpp: In function 'int main()':
foo.cpp:12:49: error: 'scanf' was not declared in this scope
     scanf("%lf%lf%lf%lf%d",&box,&c,&dic,&p[0],&N);
                                                 ^
foo.cpp:33:35: error: 'printf' was not declared in this scope
             printf("No solution\n");
                                   ^
foo.cpp:34:19: error: 'exit' was not declared in this scope
             exit(0);
                   ^
foo.cpp:53:27: error: 'printf' was not declared in this scope
     printf("%0.2lf\n",cost);
                           ^