Compilare: user.cpp: In function ‘int in_hash(int, char*, int)’: user.cpp:32:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < V[x].size(); ++ i) ^ user.cpp:33:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (strlen(a[V[x][i].first]) == l && scmp(a[V[x][i].first], s, l)) ^ user.cpp: In function ‘int In_hash(int, char*, int)’: user.cpp:43:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < V[x].size(); ++ i) ^ user.cpp:44:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (strlen(a[V[x][i].first]) == l && scmp(a[V[x][i].first], s, l)) ^ user.cpp: In function ‘void read()’: user.cpp:52:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("propozitie2.in", "r", stdin); ^ user.cpp:53:16: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s + 1); ^ user.cpp:55:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n", &m); ^ user.cpp:61:19: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(a[j]); ^ user.cpp: In function ‘void write()’: user.cpp:96:44: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("propozitie2.out", "w", stdout); ^ In file included from /usr/include/stdio.h:934:0, from /usr/include/c++/4.8/cstdio:42, from user.cpp:1: In function ‘char* gets(char*)’, inlined from ‘void read()’ at user.cpp:61:19: /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/ccdLBORF.o: In function `read()': user.cpp:(.text+0x53c): warning: the `gets' function is dangerous and should not be used. user.cpp:(.text+0x49e): warning: the `gets' function is dangerous and should not be used.