foo.cc: In function 'void workk()':
foo.cc:45:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(register int i=1;i<dl[0];i++){//在multiset中找一下 
                          ~^~~~~~
foo.cc: In function 'void workk2()':
foo.cc:57:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(register int i=1;i<dl[0];i++){
                          ~^~~~~~
foo.cc: In function 'void init()':
foo.cc:15:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d%d%d",&ts,&tt,&n,&m);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

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