foo.cc: In function 'void build(ll, ll, ll)':
foo.cc:39:10: error: 'a' was not declared in this scope
   sum[k]=a[l];
          ^
foo.cc:42:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
     ll mid=l+r>>1;
            ~^~
foo.cc: In function 'void change(ll, ll, ll, ll, ll)':
foo.cc:53:19: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  register ll mid=l+r>>1;
                  ~^~
foo.cc: At global scope:
foo.cc:58:88: error: storage class 'register' invalid for function 'query'
 register ll query(register ll k,register ll l,register ll r,register ll x,register ll y){
                                                                                        ^
foo.cc: In function 'll query(ll, ll, ll, ll, ll)':
foo.cc:61:19: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  register ll mid=l+r>>1;
                  ~^~
foo.cc: In function 'int main()':
foo.cc:87:35: error: 'updatel' was not declared in this scope
   if(t==1)read(x),read(y),read(z),updatel(x,y,z);
                                   ^~~~~~~
foo.cc:87:35: note: suggested alternative: 'updatep'
   if(t==1)read(x),read(y),read(z),updatel(x,y,z);
                                   ^~~~~~~
                                   updatep
foo.cc:89:32: error: 'updatet' was not declared in this scope
   else if(t==3)read(x),read(z),updatet(x,z);
                                ^~~~~~~
foo.cc:89:32: note: suggested alternative: 'updatep'
   else if(t==3)read(x),read(z),updatet(x,z);
                                ^~~~~~~
                                updatep
foo.cc:90:22: error: 'askt' was not declared in this scope
   else read(x),print(askt(x)),putchar('\n');
                      ^~~~
foo.cc:90:22: note: suggested alternative: 'askl'
   else read(x),print(askt(x)),putchar('\n');
                      ^~~~
                      askl

自豪的采用 HydroJudge 进行评测(github.com/hydro-dev/HydroJudge)