Java入门小题目。

发布网友发布时间：2024-03-05 08:43

共3个回答

热心网友时间：2024-08-12 16:02

int sum=1;
for(int i=1;i<20;i++){
sum+=i*2-1;
}
System.out.print(sum);
我这里没开编译器不知道对不对

热心网友时间：2024-08-12 16:06

程序：
public class Test{
public static void main(String[] args) {
int a = 1, b = 1;
int i = 0;
int temp;
int sum = a + b;
System.out.println(a);
System.out.println(b);
for (i=0; i<20; i++){
a += b;
sum += a;
System.out.println(a);
temp = b;
b = a;
a = temp;
}
System.out.println("sum : "+sum);
}
}

结果：
---------- Run Java ----------
1
1
2
3
5
8
13
21
34
55
89
144
233
377
610
987
1597
2584
4181
6765
10946
17711
sum : 46367

输出完成 (耗时: 0 秒) - 正常终止

热心网友时间：2024-08-12 16:01

//1+1+2+...+n=0+1+1+2+...+n
//0,1,2的位置分别用k,k+1,k+2
//得出:(k+(k+1))=k+2
public class Q1 {
public static void main(String[] args) {
int previous = 0, current = 1, times = 10, sum = 0;
StringBuilder sb = new StringBuilder("sum=");
for (int i = 0; i < times; i++) {
sum += current;
if (i != 0)
sb.append("+");
sb.append(current);
int tmp = previous;
previous = current;
current = tmp + current;
}
sb.append("=").append(sum);
System.out.println(sb.toString());
}
}