Compilare: user.cpp: In function ‘int main()’: user.cpp:59:22: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%c",&c); ^ user.cpp:67:49: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] nr=nr*10+c-'0';fscanf(f,"%c",&c); ^ user.cpp:74:27: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] else fscanf(f,"%c",&c); ^ user.cpp: In function ‘int construire()’: user.cpp:50:5: warning: ‘sol’ may be used uninitialized in this function [-Wmaybe-uninitialized] if(sol > 1<<30 ) return val[carpit]; ^