foo.cc: In function 'int sread(int&, std::__cxx11::string)':
foo.cc:15:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     while(c[x]<'0' || c[x]>'9'&&x<c.size()) {
                                 ~^~~~~~~~~
foo.cc:15:31: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
     while(c[x]<'0' || c[x]>'9'&&x<c.size()) {
foo.cc:14:9: warning: unused variable 'len' [-Wunused-variable]
     int len=c.size();
         ^~~
foo.cc: In function 'int geto()':
foo.cc:31:9: warning: unused variable 'len' [-Wunused-variable]
     int len=o.size();
         ^~~
foo.cc: In function 'int main()':
foo.cc:80:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&t);
     ~~~~~^~~~~~~~~
foo.cc:83:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d ",&l); getline(cin,o);
         ~~~~~^~~~~~~~~~