foo.c: In function 'main':
foo.c:19:21: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
     if (i1 % 2 == 0 && same == i2/2 ||i1 % 2 != 0 && same == (i2 - 1) / 2){
         ~~~~~~~~~~~~^~~~~~~~~~~~~~~
foo.c:8:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%c",&num[i1]);
         ^~~~~~~~~~~~~~~~~~~~

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