foo.c: In function 'main':
foo.c:7:3: error: expected ';', ',' or ')' before 'int'
    7 |   int x1,x2 ,m,n;
      |   ^~~
foo.c:4:10: warning: unused variable 'x2' [-Wunused-variable]
    4 |   int x1,x2;
      |          ^~
foo.c:4:7: warning: unused variable 'x1' [-Wunused-variable]
    4 |   int x1,x2;
      |       ^~
foo.c: At top level:
foo.c:17:3: error: expected identifier or '(' before '{' token
   17 |   {
      |   ^

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