Compilare: user.cpp: In function ‘int main()’: user.cpp:25:25: warning: format ‘%d’ expects argument of type ‘int’, but argument 3 has type ‘long long int’ [-Wformat=] fprintf(f, "%d\n", sum); ^ user.cpp:13:28: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d%d", &n, &p); ^ user.cpp:20:30: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d", &cost[i]); ^