/in/calc.cpp:188:50: error: '&&' within '||' [-Werror,-Wlogical-op-parentheses]
              (input[0] < '0' || input[0] > '9') && input[0] != '-') {
              ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~
/in/calc.cpp:188:50: note: place parentheses around the '&&' expression to silence this warning
              (input[0] < '0' || input[0] > '9') && input[0] != '-') {
                                                 ^
              (                                                    )
1 error generated.
/in/Compile/Makefile:44: recipe for target 'buildCalc' failed
make: *** [buildCalc] Error 1