计算1+12+123+1234+12345

/*计算1+12+123+1234+12345*/
#include"stdio.h"
int main()
{
    int i,item=0,sum=0;
    for(i=1;i<=5;i++){
        item=item*10+i;
        sum=sum+item;
    }
    printf("The sum of 1+12+123+1234+12345 is %d.\n",sum);
    return 0;
}