Compilare: user.cpp: In function ‘int main()’: user.cpp:73:17: warning: array subscript has type ‘char’ [-Wchar-subscripts] k2[c]++; ^ user.cpp:74:21: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(!qc[c].empty() && qc[c].back().first==k2[c]) ^ user.cpp:74:38: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(!qc[c].empty() && qc[c].back().first==k2[c]) ^ user.cpp:74:58: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(!qc[c].empty() && qc[c].back().first==k2[c]) ^ user.cpp:76:25: warning: array subscript has type ‘char’ [-Wchar-subscripts] sol[qc[c].back().second]=i; ^ user.cpp:77:21: warning: array subscript has type ‘char’ [-Wchar-subscripts] qc[c].pop_back(); ^ user.cpp:9:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("qmatrix.in","r",stdin); ^ user.cpp:10:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("qmatrix.out","w",stdout); ^ user.cpp:11:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&n,&x,&y,&q); ^ user.cpp:14:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("\n"); ^ user.cpp:15:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c ",&c); ^ user.cpp:18:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&k,&p); ^ user.cpp:23:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&k,&p); ^