/in/foo.cc: In function 'int main()':
/in/foo.cc:7:21: warning: unused variable 'x2' [-Wunused-variable]
  int n,s,f,b,d,t,x1,x2,du,max,time,c,i,t1,m,bing;
                     ^
/in/foo.cc:7:24: warning: unused variable 'du' [-Wunused-variable]
  int n,s,f,b,d,t,x1,x2,du,max,time,c,i,t1,m,bing;
                        ^
/in/foo.cc:7:38: warning: unused variable 'i' [-Wunused-variable]
  int n,s,f,b,d,t,x1,x2,du,max,time,c,i,t1,m,bing;
                                      ^