/in/foo.c: In function 'main':
/in/foo.c:15:31: error: 'j' undeclared (first use in this function)
   15 |             if (arr[i] <= arr[j]) {
      |                               ^
/in/foo.c:15:31: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:4:12: warning: unused variable 'm' [-Wunused-variable]
    4 |     int n, m;
      |            ^
/in/foo.c: At top level:
/in/foo.c:24:5: error: expected identifier or '(' before 'for'
   24 |     for (int i = 0; i < n; i++) {
      |     ^~~
/in/foo.c:24:23: error: expected '=', ',', ';', 'asm' or '__attribute__' before '<' token
   24 |     for (int i = 0; i < n; i++) {
      |                       ^
/in/foo.c:24:29: error: expected '=', ',', ';', 'asm' or '__attribute__' before '++' token
   24 |     for (int i = 0; i < n; i++) {
      |                             ^~
/in/foo.c:30:12: error: expected declaration specifiers or '...' before string constant
   30 |     printf("\n");
      |            ^~~~
/in/foo.c:32:5: error: expected identifier or '(' before 'return'
   32 |     return 0;
      |     ^~~~~~
/in/foo.c:33:1: error: expected identifier or '(' before '}' token
   33 | }
      | ^