Compilare: user.cpp: In function ‘int main()’: user.cpp:54:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(x=0;x<muchii[c1].size();x++) ^ user.cpp:65:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(x=0;x<muchii[c1].size();x++) ^ user.cpp:66:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(y=0;y<muchii[c2].size();y++) ^ user.cpp:81:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<muchii[c2].size() &&(muchii[muchii[c2][i]].size()>3 ||viz[muchii[c2][i]]==true)) i++; ^ user.cpp:96:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<muchii[c3].size() &&(muchii[muchii[c3][i]].size()>3 ||viz[muchii[c3][i]]==true)) i++; ^ user.cpp:109:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(x=0;x<muchii[c1].size();x++) ^ user.cpp:110:47: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(y=0;y<muchii[c2].size();y++) ^ user.cpp:25:24: warning: unused variable ‘c4’ [-Wunused-variable] int c1=0,c2=0,c3=0,c4=0; ^ user.cpp:12:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("puzzle2.in","r",stdin); ^ user.cpp:13:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("puzzle2.out","w",stdout); ^ user.cpp:17:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d",&n,&m); ^ user.cpp:20:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d",&x,&y); ^