/in/foo.cc: In function 'int read()':
/in/foo.cc:26:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
     for (c=gc;!isdigit(c);c=gc) if (c=='-') f=-1; x=c-'0';
     ^~~
/in/foo.cc:26:51: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
     for (c=gc;!isdigit(c);c=gc) if (c=='-') f=-1; x=c-'0';
                                                   ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:17:20: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
 #define rep(i,s,n) for (register int i=s;i<=n;i++)
                    ^
/in/foo.cc:61:5: note: in expansion of macro 'rep'
     rep(i,1,n) ans+=s[i]/v[i]; printf("%.11lf\n",ans);
     ^~~
/in/foo.cc:61:32: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
     rep(i,1,n) ans+=s[i]/v[i]; printf("%.11lf\n",ans);
                                ^~~~~~
/in/foo.cc: In function 'double solve(int, double)':
/in/foo.cc:42:12: warning: 'mid' may be used uninitialized in this function [-Wmaybe-uninitialized]
     return mid;
            ^~~