Compilare: user.cpp: In function ‘int main()’: user.cpp:29:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("disjoint.in","r",stdin); ^ user.cpp:30:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("disjoint.out","w",stdout); ^ user.cpp:32:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&que); ^ user.cpp:41:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d",&instr,&x,&y); ^ user.cpp:7:20: warning: ‘r’ may be used uninitialized in this function [-Wmaybe-uninitialized] for (; r != t[r]; r = t[r]); ^ user.cpp:6:9: note: ‘r’ was declared here int r; ^ user.cpp:7:20: warning: ‘r’ may be used uninitialized in this function [-Wmaybe-uninitialized] for (; r != t[r]; r = t[r]); ^ user.cpp:6:9: note: ‘r’ was declared here int r; ^ user.cpp:7:20: warning: ‘r’ may be used uninitialized in this function [-Wmaybe-uninitialized] for (; r != t[r]; r = t[r]); ^ user.cpp:6:9: note: ‘r’ was declared here int r; ^ user.cpp:7:20: warning: ‘r’ may be used uninitialized in this function [-Wmaybe-uninitialized] for (; r != t[r]; r = t[r]); ^ user.cpp:6:9: note: ‘r’ was declared here int r; ^