/in/foo.cc: In function 'int main()':
/in/foo.cc:25:33: warning: operation on 't' may be undefined [-Wsequence-point]
      if(a[i]) {printf("%d ",i-p[--t]-sum[i]+sum[p[t]]+1);}
                                 ^~~
/in/foo.cc:19:10: warning: unused variable 'l' [-Wunused-variable]
      int l=1,r=n*2;
          ^
/in/foo.cc:19:14: warning: unused variable 'r' [-Wunused-variable]
      int l=1,r=n*2;
              ^
/in/foo.cc:20:14: warning: unused variable 'nv' [-Wunused-variable]
      int t=1,nv=0;
              ^~