foo.c: In function 'main':
foo.c:23:21: warning: variable 't' set but not used [-Wunused-but-set-variable]
   23 |                 int t;
      |                     ^
foo.c:35:27: warning: 'decide' may be used uninitialized [-Wmaybe-uninitialized]
   35 |                         if(decide==1){
      |                           ^
foo.c:6:13: note: 'decide' was declared here
    6 |         int decide;
      |             ^~~~~~

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