/in/foo.cc: In function 'long long int read()':
/in/foo.cc:8:22: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
     while ((ch!='-') && ch<'0' || ch>'9')
            ~~~~~~~~~~^~~~~~~~~
/in/foo.cc: In function 'int c1()':
/in/foo.cc:34:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (i=0;i<s1.size();i++)//横排处理
              ~^~~~~~~~~~
/in/foo.cc:49:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int c2()':
/in/foo.cc:52:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (i=0;i<s2.size();i++)//横排处理
              ~^~~~~~~~~~
/in/foo.cc:67:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int c3()':
/in/foo.cc:70:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (i=0;i<s3.size();i++)//横排处理
              ~^~~~~~~~~~
/in/foo.cc:85:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int r1()':
/in/foo.cc:106:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int r2()':
/in/foo.cc:127:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int r3()':
/in/foo.cc:148:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int x1()':
/in/foo.cc:169:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int x2()':
/in/foo.cc:190:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int tot()':
/in/foo.cc:193:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (i=0;i<s1.size();i++)
              ~^~~~~~~~~~
/in/foo.cc:200:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (i=0;i<s2.size();i++)
              ~^~~~~~~~~~
/in/foo.cc:207:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (i=0;i<s3.size();i++)
              ~^~~~~~~~~~
/in/foo.cc:214:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^