模拟数的进位运算

解题思路:如下

注意事项:

参考代码:

#include<stdio.h>

int main(){

             int n,r;

             scanf("%d%d",&n,&r);

             char m[r],k=1;

             for(int i=0;i<r;i++){

                 m[i]=i+1;

             }

             for(int k=0;;k++){

                 for(int i=0;i<r;i++){

                     printf("%3d",m[i]); 

            }

                 printf("\n");

                 if(m[0]==n-r+1){

                     break;

                 }

                 if(m[r-1]==n){

                     for(int j=0;j<r;j++){

                         if((m[j]==n-r+1+j)&&j==r-1){

                                 m[r-2]++;

                                 m[r-1]=m[r-2];

                                 break;

                         }else if((m[j]==n-r+1+j)&&j!=r-1){

                                 m[j-1]++;

                                 for(int f=j;f<r;f++){

                                      m[f]=m[j-1]+f-j+1;

                                 }

                                 m[r-1]--;

                                 break;

                         }

                     }

                 }

                 m[r-1]++;

             }

             return 0;

}