Compilare: main.cpp: In function 'void solve(int)': main.cpp:13:7: warning: variable 'a' set but not used [-Wunused-but-set-variable] int a, b ; ^ main.cpp:13:10: warning: variable 'b' set but not used [-Wunused-but-set-variable] int a, b ; ^ main.cpp: In function 'int main()': main.cpp:36:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("diagonala.in", "r", stdin) ; ^ main.cpp:37:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("diagonala.out", "w", stdout) ; ^ main.cpp:39:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n) ; ^ main.cpp:41:40: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &v[i].fi, &v[i].se) ; ^