Compilare: main.cpp: In function 'int main()': main.cpp:15:47: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d %d %d %d\n", &n, &p, &q, &m); ^ main.cpp:20:37: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d %d\n", &x, &y); ^ main.cpp:39:9: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized] int ans; ^~~