Compilare: main.cpp: In function 'void ec1()': main.cpp:29:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while( i < a.size() ) ~~^~~~~~~~~~ main.cpp: In function 'void ec2()': main.cpp:51:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while( i < a.size() ) ~~^~~~~~~~~~ main.cpp:63:7: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses] if( x != 0 && del >= 0 && sqrt( del ) == ( pp = ( int )sqrt( del ) ) ) ^