Compilare: main.cpp: In function 'int main()': main.cpp:54:26: warning: format '%s' expects argument of type 'char*', but argument 3 has type 'char (*)[21]' [-Wformat=] fscanf(fin, "%s", &op); ^ main.cpp:50:24: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d", &n); ^ main.cpp:54:27: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%s", &op); ^