Compilare: user.cpp: In function ‘void lee()’: user.cpp:35:53: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if (a[xx][yy]>=k2||a[xx][yy]<=k1&&(sol[xx][yy]==-1||sol[xx][yy]>sol[X.f.f][X.f.s]+1)) ^ user.cpp: In function ‘int main()’: user.cpp:89:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("vis.in","r",stdin); ^ user.cpp:90:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("vis.out","w",stdout); ^ user.cpp:91:63: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d %d %d %d %d\n",&n,&k1,&k2,&x1,&Y1,&x2,&y2); ^ user.cpp:95:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i][j]); ^