#include <stdio.h>
#include <stdlib.h>

typedef struct{
    char c;
    int h;
}structure;

int q(const void *a,const void *b)
{
    if(((structure*)b)->h>((structure*)a)->h)return 1;
    else return -1;
}

int main(void)
{
    int i;
    structure d[3]={{'A'},{'B'},{'C'}};
    for(i=0;i<3;++i)scanf("%d",&d[i].h);
    qsort(d,3,sizeof(structure),q);
    for(i=0;i<3;++i)printf("%c\n",d[i].c);
    return 0;
}