public class hg {

public static void main(String[] args){

int scores[]={61,23,4,74,13,148,20};

int max=scores[0];

int main=scores[6];

double sum=0;  （这里是整数求和 为什么用double 不用int？？？？？？？？）

double avg=0;

for(int i=0;i<=scores.length;i++)

少循环一次

改为 i<scores.length

public static void main(String[] args) {

int scores[] = { 61, 23, 4, 74, 13, 148, 20 };

int max = scores[0],min = scores[0];

double sum = 0;

double avg = 0;

for (int i = 0; i <= scores.length-1; i++) {

if (max < scores[i]) {

max = scores[i];

} 

if (min > scores[i]) {

min = scores[i];

}

sum = sum + scores[i];

}

avg = sum / scores.length;

System.out.println(sum);

System.out.println(avg);

System.out.println(max);

System.out.println(min);

}

public static void main(String[] args) {

int scores[] = { 61, 23, 4, 74, 13, 148, 20 };

int max = scores[0];

int main = scores[6];

double sum = 0;

double avg = 0;

for (int i = 0; i <= scores.length-1; i++) {

if (max < scores[i]) {

max = scores[i];

} else if (main > scores[i]) {

main = scores[i];

}

sum = sum + scores[i];

}

avg = sum / scores.length;

System.out.println(sum);

System.out.println(avg);

}

main可以

不要用main吧。。main可以用？

不能等于代码长度