#include <stdio.h>

int main(void) {
int i,a[]={3,5,2,4,1,9,7,6,0,8};
int max=-1,maxi=-1;
int second=-1,secondi=-1;
double sum=0;
for(i=0;i<10;i++){
	sum+=a[i];
	if(a[i]>max){
		second=max;
		secondi=maxi;
		max=a[i];
		maxi=i;
	}
	else if(a[i]>second){
		second=a[i];
		secondi=i;
	}
}
printf("最大値:%d(場所:a[%d])\n",max,maxi);
printf("二番目に大きい値:%d(場所:a[%d])\n",second,secondi);
printf("全要素の平均値:%.lf\n",sum/10.0);
	return 0;
}