Compilare: user.cpp: In function ‘int main()’: user.cpp:124:31: warning: unused variable ‘j’ [-Wunused-variable] int m, i, lim, st, dr, k, j; ^ user.cpp:122:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ( "rev.in", "r", stdin ); ^ user.cpp:123:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ( "rev.out", "w", stdout ); ^ user.cpp:125:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d", &n ); ^ user.cpp:129:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d", &m ); ^ user.cpp:132:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d%d%d", &st, &dr, &k ); ^