#include <stdio.h>

int main(void){
    int i = 1, j, tmp, n[10] = {0}, len = 0, maxnum = 0;
    while(1){
        n[i] = getchar();
        if(n[i]=='\n') break;
        n[i] -= '0';
        if(n[i]>maxnum){
            maxnum = n[i];
        }
        i++;
    }
    len = i - 1;
    for(i=len;i>=1;i--){
        if(n[i]==maxnum) break;
    }
    for(j=1;j<=len;j++){
        if(n[j]!=maxnum){
            tmp = n[j];
            n[j] = maxnum;
            n[i] = tmp;
            break;
        }
    }
    for(i=1;i<=len;i++){
        printf("%d", n[i]);
    }
    printf("\n");
    return 0;
}