Compilare: main.cpp: In function 'int main()': main.cpp:18:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d\n", &n, &m); ^ main.cpp:22:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%c %c\n", &a, &b); ^