Compilare: user.cpp: In function ‘int main()’: user.cpp:89:24: warning: narrowing conversion of ‘i’ from ‘int’ to ‘short int’ inside { } [-Wnarrowing] vals[nr++] = {v[i].first, v[i].second, i}; ^ user.cpp:33:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j; ^ user.cpp:34:10: warning: unused variable ‘ch’ [-Wunused-variable] char ch; ^ user.cpp:38:27: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(s, 2 * MAXL, fi); ^