#include<stdio.h>
int main(int a,int b,int c){
    if(a<=b && a<=c)return a;
    if(b<=a && b<=c)return b;
    return c;
}
int minTurns(int score){
    if (score == 0)return 0;
    if (score < 0)return 1000;
    return 1 + min(minTurns(scroe-1),minTurns(score-2)minTurns(score-3));
}
int main(){
    float input;
    scanf("%f",&input);
    if(input<0){
        printf("Invalid Input");
        return 0;
    }
    int score=(int)input;
    int result=minTurns(score);
    printf("%d\n",result);
    return 0;
}