Compilare: user.cpp: In function ‘int main()’: user.cpp:37:15: warning: unused variable ‘j’ [-Wunused-variable] int n,m,i,j,x,y,c; ^ user.cpp:35:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("apm.in","r",stdin); ^ user.cpp:36:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("apm.out","w",stdout); ^ user.cpp:38:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:43:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&x,&y,&c); ^ user.cpp:40:22: warning: iteration 100001u invokes undefined behavior [-Waggressive-loop-optimizations] h[i]=1,t[i]=i; ^ user.cpp:39:5: note: containing loop for(i=0;i<=200000;++i) ^