#include <stdio.h>
int main( void )
{int n, i = 0, m, p,ans;scanf("%d%d", &n, &m); //n总人数，m步长while( ++i <= n ){p = i * m;while (p > n)p = p - n + (p - n - 1)/(m - 1);//  printf("%d\n", p);ans=p;}printf("%d\n",ans);return 0;
}/***************************************************
User name: TJRAC6015203228魏杰
Result: Accepted
Take time: 0ms
Take Memory: 104KB
Submit time: 2016-11-01 13:56:54
****************************************************/