/in/foo.c: In function 'f':
/in/foo.c:42:8: warning: unused variable 'k' [-Wunused-variable]
  int j,k;
        ^
/in/foo.c:42:6: warning: unused variable 'j' [-Wunused-variable]
  int j,k;
      ^
/in/foo.c: In function 'main':
/in/foo.c:92:17: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
     if((i+4<len)&&
        ~~~~~~~~~^~
      (s[i+2]=='F'&&(s[i+4]=='M'||s[i+4]=='1')&&s[i+3]=='D')||
      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/in/foo.c:62:29: warning: unused variable 'flag' [-Wunused-variable]
  int a,b,c,d,m,n,i,j,k,l,ss,flag;
                             ^~~~
/in/foo.c:62:24: warning: unused variable 'l' [-Wunused-variable]
  int a,b,c,d,m,n,i,j,k,l,ss,flag;
                        ^
/in/foo.c:62:22: warning: unused variable 'k' [-Wunused-variable]
  int a,b,c,d,m,n,i,j,k,l,ss,flag;
                      ^
/in/foo.c:62:20: warning: unused variable 'j' [-Wunused-variable]
  int a,b,c,d,m,n,i,j,k,l,ss,flag;
                    ^
/in/foo.c:62:14: warning: unused variable 'm' [-Wunused-variable]
  int a,b,c,d,m,n,i,j,k,l,ss,flag;
              ^
/in/foo.c:62:12: warning: unused variable 'd' [-Wunused-variable]
  int a,b,c,d,m,n,i,j,k,l,ss,flag;
            ^
/in/foo.c:62:10: warning: unused variable 'c' [-Wunused-variable]
  int a,b,c,d,m,n,i,j,k,l,ss,flag;
          ^
/in/foo.c:62:8: warning: unused variable 'b' [-Wunused-variable]
  int a,b,c,d,m,n,i,j,k,l,ss,flag;
        ^
/in/foo.c:62:6: warning: unused variable 'a' [-Wunused-variable]
  int a,b,c,d,m,n,i,j,k,l,ss,flag;
      ^