Accepted
/in/foo.cc: In function 'int main()':
/in/foo.cc:44:5: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses]
if (s1[b]) if (ans==-1) ans=s1[b];else ans=min(ans,s1[b]);
^
/in/foo.cc:45:5: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses]
if (s2[a]) if (ans==-1) ans=s2[a];else ans=min(ans,s2[a]);
^
