foo.c: In function 'main':
foo.c:15:25: error: expected declaration or statement at end of input
   15 |                         x1=x1+1;
      |                         ^~
foo.c:15:25: error: expected declaration or statement at end of input
foo.c:15:25: error: expected declaration or statement at end of input
foo.c:7:9: warning: unused variable 'n' [-Wunused-variable]
    7 |     int n=0;
      |         ^

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