Compilare: user.cpp: In function ‘void solve(int, int)’: user.cpp:27:19: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if(a[d.front()]+b[j-i+d.front()]==sol) ^ user.cpp: In function ‘int main()’: user.cpp:50:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("secv2m.in","r",stdin); ^ user.cpp:51:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("secv2m.out","w",stdout); ^ user.cpp:52:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&n,&m,&l); ^ user.cpp:55:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&a[i]); ^ user.cpp:57:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&b[j]); ^