Rezumat problemă

Expresie3

#335

Să se scrie un program care citește numărul natural n și determină suma S=1*2-2*3+3*4-...±n*(n+1).

Consola Candale Silviu (silviu) ușoară

Clasa 9 Algoritmi elementari Sume, produse, numărări

Rezolvă

Detalii

Problema	Expresie3	Operații I/O	tastatură/ecran
Limita timp	0.1 secunde	Limita memorie	Total: 64 MB / Stivă 8 MB
Id soluție	#64190284	Utilizator	Horea Nadia (nadiahorea)
Fișier	expresie3.cpp	Dimensiune	247 B
Data încărcării	22 Aprilie 2026, 10:37	Scor/rezultat	Eroare de compilare

Evaluare

Mesaj compilare

expresie3.cpp:1:9: error: #include expects "FILENAME" or <FILENAME>
    1 | #include,iostream>
      |         ^
expresie3.cpp: In function ‘int main()’:
expresie3.cpp:5:5: error: ‘cin’ was not declared in this scope
    5 |     cin>>n;
      |     ^~~
expresie3.cpp:1:1: note: ‘std::cin’ is defined in header ‘<iostream>’; did you forget to ‘#include <iostream>’?
  +++ |+#include <iostream>
    1 | #include,iostream>
expresie3.cpp:6:9: error: ‘it’ was not declared in this scope; did you mean ‘int’?
    6 |     for(it =1;i<=n;i++)
      |         ^~
      |         int
expresie3.cpp:6:15: error: ‘i’ was not declared in this scope
    6 |     for(it =1;i<=n;i++)
      |               ^
expresie3.cpp:6:5: warning: this ‘for’ clause does not guard... [-Wmisleading-indentation]
    6 |     for(it =1;i<=n;i++)
      |     ^~~
expresie3.cpp:11:9: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the ‘for’
   11 |         cout<<"Rezultatut este ";
      |         ^~~~
expresie3.cpp:11:9: error: ‘cout’ was not declared in this scope
expresie3.cpp:11:9: note: ‘std::cout’ is defined in header ‘<iostream>’; did you forget to ‘#include <iostream>’?

Cum funcționează evaluarea?