基础 ">#include<string.h> #include<algorithm> using namespace std; char a[1000],b[100]; int n; bool book[100]={0}; void dfs(int step) { int i; if(step==n) { printf("%s\n",b); } for(i=0;i<n;i++) { if(book[i]==0) { book[i]=1; b[step]=a[i]; dfs(step+1); book[i]=0; } } } int main() { scanf(...