Compilare: user.cpp: In function ‘int main()’: user.cpp:36:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("seti.in","r",stdin); ^ user.cpp:37:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("seti.out","w",stdout); ^ user.cpp:38:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n", &n); ^ user.cpp:42:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c",&a[j+(i-1)*64]); ^ user.cpp:43:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] if (j==64)scanf("\n"); ^ user.cpp:45:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n", &m); ^ user.cpp:50:22: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(ss[i]+1); ^ In file included from /usr/include/stdio.h:934:0, from /usr/include/c++/4.8/cstdio:42, from /usr/include/i386-linux-gnu/c++/4.8/bits/stdc++.h:46, from user.cpp:1: In function ‘char* gets(char*)’, inlined from ‘int main()’ at user.cpp:50:22: /usr/include/i386-linux-gnu/bits/stdio2.h:230:28: warning: call to ‘__gets_warn’ declared with attribute warning: please use fgets or getline instead, gets can't specify buffer size [enabled by default] return __gets_warn (__str); ^ /tmp/ccpFnnD7.o: In function `main': user.cpp:(.text.startup+0x112): warning: the `gets' function is dangerous and should not be used.