/in/lab5.c: In function 'infixtopostfix':
/in/lab5.c:130:33: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
         else if (expr[i] >= '0' && expr[i] <= '9'|| expr[i] == '.') {
                  ~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~
/in/lab5.c:115:9: warning: unused variable 'j' [-Wunused-variable]
     int j = 0;
         ^