foo.c: In function 'main':
foo.c:32:9: warning: implicit declaration of function 'qsort' [-Wimplicit-function-declaration]
   32 |         qsort(a,m,sizeof(int),compare);
      |         ^~~~~
foo.c:15:43: warning: unused variable 'result' [-Wunused-variable]
   15 |         int m,n,a[2000]={0},sum,i,j,k,t,r,result;
      |                                           ^~~~~~
foo.c:15:39: warning: unused variable 't' [-Wunused-variable]
   15 |         int m,n,a[2000]={0},sum,i,j,k,t,r,result;
      |                                       ^
foo.c:15:37: warning: unused variable 'k' [-Wunused-variable]
   15 |         int m,n,a[2000]={0},sum,i,j,k,t,r,result;
      |                                     ^

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