计算2+22+222+2222

P137
计算2+22+222+2222

#include
#include
void main(){int a,n;scanf("%d,%d",&a,&n);int i,tn=0,sn=0;for(i=1;i<=n;i++){tn=tn+a;sn=sn+tn;a=a*10;}printf("%d",sn);
}