#include int pl(int n) { int a[100]; int flag=1; FILE *rf ; int i,j,k,x,count=0; rf = fopen("pl.txt", "w") ; for (i=1;i<=n;i++) a[i]=i; while (flag) /* 还剩余未输出的排列*/ { for (i=1;i<=n;i++) /* 输出当前排列 */ { printf("%4d",a[i]); fprintf(rf,"%4d",a[i]);} printf("\n"); fprintf(rf,"\n"); count++; /*计数器加1*/ i=n; /*从后向前找相邻位置后大前小的元素值*/ while (i>1 && a[i]j && a[i]=k && x