foo.cc: In function ‘int main()’:
foo.cc:11:22: error: ‘P’ was not declared in this scope
   11 |                 case P:jg=jg*0.7;break;
      |                      ^
foo.cc:12:22: error: ‘G’ was not declared in this scope
   12 |                 case G:jg=jg*0.8;break;
      |                      ^
foo.cc:13:22: error: ‘S’ was not declared in this scope
   13 |                 case S:jg=jg*0.9;break;
      |                      ^