Compilare: user.cpp: In function ‘int main()’: user.cpp:218:26: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d", &n); ^ user.cpp:219:64: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(int i=1; i<=n; i++) fscanf(fin, "%lf%lf", &a[i], &b[i]); ^ user.cpp:220:64: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(int i=1; i<=n; i++) fscanf(fin, "%lf%lf", &x[i], &y[i]); ^ user.cpp:203:26: warning: ‘ans’ may be used uninitialized in this function [-Wmaybe-uninitialized] ans+=dist[destin]; ^ user.cpp:200:12: note: ‘ans’ was declared here double ans; ^