代码

#pragma GCC optimize("Ofast")
void f(unsigned*a,unsigned*b,int c,int d){int e[256]{};for(int f=0;f<c;f++)e[a[f]>>d&255]++;for(int f=1;f<256;f++)e[f]+=e[f-1];for(int f=c;f--;)b[--e[a[f]>>d&255]]=a[f];}
void sort(unsigned*a,int b){unsigned c[b];f(a,c,b,0),f(c,a,b,8),f(a,c,b,16),f(c,a,b,24);}

评测结果