Compilare: main.cpp: In function 'int main()': main.cpp:54:24: warning: unused variable 'val' [-Wunused-variable] int i,max1=0,a,b,c,val; ^~~ main.cpp: In function 'char next_ch()': main.cpp:13:32: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buff,1,dim,stdin); ^ main.cpp: In function 'int main()': main.cpp:49:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("radixsort.in","r",stdin); ^ main.cpp:50:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("radixsort.out","w",stdout); ^