Compilare: main.cpp: In function 'int main()': main.cpp:9:17: warning: variable 'x' set but not used [-Wunused-but-set-variable] int n,vf=-1,x; ^ main.cpp:7:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("xspe.in","r",stdin); ^ main.cpp:8:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("xspe.out","w",stdout); ^ main.cpp:10:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ main.cpp:12:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&v[j]); ^ main.cpp:28:19: warning: array subscript is below array bounds [-Warray-bounds] s[vf++]=v[i]; ~~~~~~^