foo.cc: In function 'int myAtoi(std::string)':
foo.cc:10:6: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   10 |  if(i==s.length()||(s[i]>'9'||s[i]<'0')&&s[i]!='+'&&s[i]!='-'){
      |     ~^~~~~~~~~~~~
foo.cc:10:51: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   10 |  if(i==s.length()||(s[i]>'9'||s[i]<'0')&&s[i]!='+'&&s[i]!='-'){
      |                    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~
foo.cc:20:11: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   20 |  for(i=i;i<s.length();i++){
      |          ~^~~~~~~~~~~
foo.cc:6:29: warning: unused variable 'a' [-Wunused-variable]
    6 |  long long sum=0,i=0,flag=1,a=-2147483648;
      |                             ^

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