java - 获取旧数字的整数之和 1 + (1 + 2) + (1 + 2 + 3) + ... + (1 + 2 + 3 + ... + n)

Question

我正在努力达到这个目标:

1 + (1 + 2) + (1 + 2 + 3) + ... + (1 + 2 + 3 + ... + n)

我已经得到了这个结果:-

(1 + 2) + (2 + 3)

使用此代码:

int n = 8;
for (int i = 1; i < n; i++){
     int j = i + 1;
     System.out.print("(" + i + " + " +  j + ")");
}

如何才能获得最佳结果？

Answer 1

你需要两个这样的循环:

int n = 8;

String del;
String del2 = "";

for (int i = 1; i <= n; i++) {
    System.out.print(del2 + "(");
    del = "";
    for (int j = 1; j <= i; j++) {
        System.out.print(del + j);
        del = " + ";
    }
    System.out.print(")");
    del2 = " + ";
}

code demo