Compilare: user.cpp: In function ‘void get_ans()’: user.cpp:53:9: warning: unused variable ‘t’ [-Wunused-variable] int t = 0; ^ user.cpp: In function ‘void write()’: user.cpp:91:13: warning: unused variable ‘q’ [-Wunused-variable] int q = C[s[j]].x; ^ user.cpp: In function ‘void read()’: user.cpp:35:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &k); ^ user.cpp:38:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &v[i]); ^ user.cpp: In function ‘void write()’: user.cpp:110:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ksort.out", "w", stdout); ^