Compilare: main.cpp: In function 'bool back(int, int*)': main.cpp:10:9: warning: variable 'b' set but not used [-Wunused-but-set-variable] int b[20]; ^ main.cpp: In function 'int main()': main.cpp:32:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("carti.in", "r", stdin); ^ main.cpp:33:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("carti.out", "w", stdout); ^ main.cpp:35:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t); ^ main.cpp:37:32: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d\n", &n, &k); ^ main.cpp:40:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%c", &c1); ^ main.cpp:41:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%c", &c2); ^ main.cpp:42:51: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] if(c2 != ' ' && c2 != '\n') scanf(" "); ^