/in/foo.c: In function 'main':
/in/foo.c:11:5: error: expected ';' before 'printf'
     printf("y1=x1+x2=%d",y1);
     ^~~~~~
/in/foo.c:6:6: warning: variable 'y1' set but not used [-Wunused-but-set-variable]
  int y1,y2,y3;
      ^~