foo.cc: In function 'void dts::main()':
foo.cc:152:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i=0;i<x.size();i++)
                ~^~~~~~~~~
foo.cc:157:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    if (i<x.size())
        ~^~~~~~~~~
foo.cc: In function 'int dts::search(int)':
foo.cc:131:2: warning: control reaches end of non-void function [-Wreturn-type]
  }
  ^
foo.cc: In function 'void dts::main()':
foo.cc:135:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d",&n,&q);
   ~~~~~^~~~~~~~~~~~~~
foo.cc:139:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d",&ctl[i]);
    ~~~~~^~~~~~~~~~~~~~
foo.cc:141:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d",&pos[i],&val[i]);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:143:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&val[i]);
     ~~~~~^~~~~~~~~~~~~~
foo.cc:145:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&pos[i]);
     ~~~~~^~~~~~~~~~~~~~
foo.cc:168:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&t);
   ~~~~~^~~~~~~~~
foo.cc:170:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d%d",&a[i],&b[i]);
    ~~~~~^~~~~~~~~~~~~~~~~~~~