Eroare de compilare: main.cpp: In function 'int main()': main.cpp:9:5: error: expected initializer before 'long' 9 | long long x,y,x1,y1,s=0; | ^~~~ main.cpp:11:10: error: 'x1' was not declared in this scope 11 | cin>>x1>>y1; | ^~ main.cpp:11:14: error: 'y1' was not declared in this scope 11 | cin>>x1>>y1; | ^~ main.cpp:12:9: error: 'i' was not declared in this scope 12 | for(i=2;i<=n;i++) | ^ main.cpp:14:9: error: 'x' was not declared in this scope 14 | cin>>x>>y; | ^ main.cpp:14:12: error: 'y' was not declared in this scope 14 | cin>>x>>y; | ^ main.cpp:15:4: error: 's' was not declared in this scope 15 | s+=x*y1-x1*y; | ^ main.cpp:20:11: error: 's' was not declared in this scope 20 | cout<<s/2; | ^ Non zero exit status: 1