Compilare: user.cpp: In function ‘void solve()’: user.cpp:37:17: warning: unused variable ‘x’ [-Wunused-variable] int x = m1[sum]; ^ user.cpp:38:17: warning: unused variable ‘y’ [-Wunused-variable] int y = m1[L-sum]; ^ user.cpp:47:13: warning: unused variable ‘x’ [-Wunused-variable] int x = m1[L-(a[i]<<1)]; ^ user.cpp: In function ‘void read()’: user.cpp:15:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &c, &L); ^ user.cpp:17:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i]); ^ user.cpp: In function ‘int main()’: user.cpp:58:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("oite.in", "r", stdin); ^ user.cpp:59:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("oite.out", "w", stdout); ^