foo.c: In function 'main':
foo.c:6:19: warning: format '%c' expects argument of type 'char *', but argument 3 has type 'int *' [-Wformat=]
    6 |         scanf("%d%c%d",&a,&t,&b);
      |                  ~^       ~~
      |                   |       |
      |                   char *  int *
      |                  %lc
foo.c:7:12: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
    7 |         if(t='+')
      |            ^
foo.c:9:17: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
    9 |         else if(t='-')
      |                 ^

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