Compilare: user.cpp: In function ‘int main()’: user.cpp:29:50: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d%d%d%d%d", &n, &e, &f, &l, &c); ^ user.cpp:32:42: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d%d%d", &f, &l, &c); ^ user.cpp:39:38: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d", &x); ^ user.cpp:94:17: warning: ‘start’ may be used uninitialized in this function [-Wmaybe-uninitialized] viz[start]=1; ^