Compilare: main.cpp: In function 'int main()': main.cpp:117:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("deletegcd.in","r",stdin); ^ main.cpp:118:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("deletegcd.out","w",stdout); ^ main.cpp: In function 'void read_vals()': main.cpp:79:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&q); ^ main.cpp:80:44: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] for(int i=1;i<=n;i++) scanf("%d",&v[i]); ^ main.cpp: In function 'void solve()': main.cpp:92:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^