Compilare: user.cpp: In function ‘void frecv_and_sum()’: user.cpp:18:22: warning: array subscript has type ‘char’ [-Wchar-subscripts] frecv[0][s[i]]++; ^ user.cpp: In function ‘int main()’: user.cpp:141:21: warning: array subscript has type ‘char’ [-Wchar-subscripts] frS[s[n]]+=suma[n][s[n]]; ^ user.cpp:141:36: warning: array subscript has type ‘char’ [-Wchar-subscripts] frS[s[n]]+=suma[n][s[n]]; ^ user.cpp:142:46: warning: array subscript has type ‘char’ [-Wchar-subscripts] fprintf(g,"%c %d\n",s[n],frS[s[n]]); ^ user.cpp:146:21: warning: array subscript has type ‘char’ [-Wchar-subscripts] frC[s[n]]+=suma[n][s[n]]; ^ user.cpp:146:36: warning: array subscript has type ‘char’ [-Wchar-subscripts] frC[s[n]]+=suma[n][s[n]]; ^ user.cpp:148:53: warning: array subscript has type ‘char’ [-Wchar-subscripts] fprintf(g,"%c %d\n",s[n]+32,frC[s[n]]); ^ user.cpp:150:53: warning: array subscript has type ‘char’ [-Wchar-subscripts] fprintf(g,"%c %d\n",s[n]-32,frC[s[n]]); ^ user.cpp: In function ‘long long int solve(long long int)’: user.cpp:125:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:130:34: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%lld %lld\n",&k,&q); ^ user.cpp:131:24: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(s+1,100002,f); ^ user.cpp:136:28: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%lld",&n); ^