Compilare: user.cpp: In function ‘int main()’: user.cpp:67:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(size_t i = 0; i < n; ++i){ ^ user.cpp:73:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(size_t i = 0; i < m; ++i){ ^ user.cpp:80:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(size_t i = 0; i < e; ++i){ ^ user.cpp:63:13: warning: unused variable ‘a’ [-Wunused-variable] long long a, b,c,x,y; ^ user.cpp:63:16: warning: unused variable ‘b’ [-Wunused-variable] long long a, b,c,x,y; ^ user.cpp:63:18: warning: unused variable ‘c’ [-Wunused-variable] long long a, b,c,x,y; ^ user.cpp:63:20: warning: unused variable ‘x’ [-Wunused-variable] long long a, b,c,x,y; ^ user.cpp:63:22: warning: unused variable ‘y’ [-Wunused-variable] long long a, b,c,x,y; ^