Compilare: user.cpp: In function ‘int main()’: user.cpp:24:24: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d",&n,&m); ^ user.cpp:25:41: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for (i=1;i<=n;i++) {fscanf(f,"%d",&v[i]); ^ user.cpp:28:32: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] while (m!=0) {fscanf(f,"%d",&k); ^ user.cpp:29:49: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] if (k==0) {fscanf(f,"%d %d",&a,&b); ^ user.cpp:32:49: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] if (k==1) {fscanf(f,"%d %d",&a,&b); ^ user.cpp:34:43: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] if (k==2) {fscanf(f,"%d",&a); ^ user.cpp:42:26: warning: ‘s’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (s!=a) fprintf(g,"-1\n"); ^