Compilare: main.cpp: In function 'int main()': main.cpp:36:21: warning: unused variable 'j' [-Wunused-variable] int n,x,y,z,m,i,j; ^ main.cpp:34:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("arbint.in","r",stdin); ^ main.cpp:35:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("arbint.out","w",stdout); ^ main.cpp:37:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ main.cpp:40:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&v[i]);update(1,1,n,i,v[i]); ^ main.cpp:44:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&x,&y,&z); ^