Compilare: user.cpp: In function ‘int find_v(int)’: user.cpp:12:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int k=0;k!=h[ind].size();k++) ^ user.cpp: In function ‘void finda(int)’: user.cpp:18:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int k=0;k!=h[ind].size();k++) ^ user.cpp: In function ‘void insert_v(int)’: user.cpp:24:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(k==h[ind].size()){ ^ user.cpp: In function ‘int find_v(int)’: user.cpp:14:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:31:29: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] {freopen("eqs.in","r",stdin); ^ user.cpp:32:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("eqs.out","w",stdout); ^ user.cpp:33:44: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d %d %d",&a1,&a2,&a3,&a4,&a5); ^