Compilare: user.cpp: In function ‘char nextch()’: user.cpp:10:36: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buf, BUF_SIZE, 1, fi); ^ user.cpp: In function ‘int main()’: user.cpp:39:12: warning: array subscript is above array bounds [-Warray-bounds] a[first]=b[n-1]; ^ user.cpp:41:26: warning: array subscript is above array bounds [-Warray-bounds] a[first-1]=a[last]; ^ user.cpp:41:18: warning: array subscript is above array bounds [-Warray-bounds] a[first-1]=a[last]; ^ user.cpp:43:18: warning: array subscript is above array bounds [-Warray-bounds] a[first-2]=b[i]; ^ user.cpp:47:31: warning: array subscript is above array bounds [-Warray-bounds] fprintf(fo,"%d ", a[i]); ^