foo.c: In function 'main':
foo.c:9:15: warning: statement with no effect [-Wunused-value]
    9 |         for(sn<=k;n++)
      |             ~~^~~
foo.c:9:22: error: expected ';' before ')' token
    9 |         for(sn<=k;n++)
      |                      ^
      |                      ;

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