/in/foo.cc: In member function 'BigInt BigInt::operator+(const BigInt&)':
/in/foo.cc:154:18: warning: variable 'shorterBit' set but not used [-Wunused-but-set-variable]
   int longerBit, shorterBit;//比较两个加数的位数大小
                  ^~~~~~~~~~
/in/foo.cc: In function 'int main(int, char**)':
/in/foo.cc:24:20: warning: 'bi.BigInt::value' may be used uninitialized in this function [-Wmaybe-uninitialized]
    value[bitNum++] = x % 10;
    ~~~~~~~~~~~~~~~~^~~~~~~~
/in/foo.cc:222:9: note: 'bi.BigInt::value' was declared here
  BigInt bi(x), ans(1);
         ^~
/in/foo.cc:24:20: warning: 'ans.BigInt::value' is used uninitialized in this function [-Wuninitialized]
    value[bitNum++] = x % 10;
    ~~~~~~~~~~~~~~~~^~~~~~~~
/in/foo.cc:222:16: note: 'ans.BigInt::value' was declared here
  BigInt bi(x), ans(1);
                ^~~
/in/foo.cc:67:14: warning: 'res.BigInt::value' may be used uninitialized in this function [-Wmaybe-uninitialized]
     value[i] = bi.value[i];
     ~~~~~~~~~^~~~~~~~~~~~~
/in/foo.cc:78:10: note: 'res.BigInt::value' was declared here
   BigInt res(0);
          ^~~