Compilare: user.cpp: In function ‘int main()’: user.cpp:126:15: warning: unused variable ‘j’ [-Wunused-variable] int n,q,i,j,x,y,z; ^ user.cpp:126:21: warning: unused variable ‘z’ [-Wunused-variable] int n,q,i,j,x,y,z; ^ user.cpp:124:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rafaela.in","r",stdin); ^ user.cpp:125:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rafaela.out","w",stdout); ^ user.cpp:128:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&q); ^ user.cpp:131:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^ user.cpp:143:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n",&val[i]); ^ user.cpp:152:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c",&ch); ^ user.cpp:155:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n",&x); ^ user.cpp:160:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d\n",&x,&y); ^ user.cpp: In function ‘void df2(int, int)’: user.cpp:48:9: warning: ‘j’ may be used uninitialized in this function [-Wmaybe-uninitialized] if(i!=j) ^