#include<stdio.h>int main(){    int n=0;    scanf("%d",&n);    if(n<1||n>100000)    {    }    else    {        for(int i=1;i<=n;i++)        {            int a=0,b=0,c=0,d=0,e=0;            a=i%10;            b=i/10%10;            c=i/100%10;            d=i/1000%10;            e=i/10000%10;            if((i%3==0)&&(a==5||b==5||c==5||d==5||e==5))            {                printf("%d\n",i);            }        }     }    return 0;}

#include<stdio.h>int main(){ int n=0,sum=0,i=1,j=1,result=0; scanf("%d",&n); for(;j<=n;j++) { for(;i<=j;i++) { sum+=i; } result+=sum;  }  printf("%d",result); return 0;}

#include<stdio.h>int main(){ int n=0,result=0;; scanf("%d",&n); if(n%2==0) { result=-n/2; } else{ result=(n+1)/2; } printf("%d",result); return 0;}

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