foo.c: In function 'main':
foo.c:7:19: warning: format '%d' expects argument of type 'int *', but argument 3 has type 'char *' [-Wformat=]
    7 |         scanf("%d%d%d",&a,&b,&c);
      |                  ~^       ~~
      |                   |       |
      |                   int *   char *
      |                  %hhd
foo.c:8:8: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
    8 |     if(b='+')
      |        ^
foo.c:10:17: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   10 |         else if(b='-')
      |                 ^

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