#include <stdio.h>
int main(){
int n;
if (scanf("%d",&n)!=EOF){
if (n==1){printf("1");}
else{
for (int i=1;i<=n;i++){printf("%d ",i);}
for (int i=n-1;i>1;i--){printf("%d ",i);}
printf("1");
}
}
else{
printf("input wrong");
}
return 0;
}
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