c++ - 如何创建正确的嵌套循环？

Question

An array is given for 15 values. Take the absolute values for every three numbers in the array, going one after the other, and calculate the area of a triangle with sides, the values of which correspond to the taken numbers. Create a new array in which to enter the values of the resulting areas. Display all areas on the screen:

我知道如何计算面积等。但是我不知道如何组织正确的嵌套循环。
你能解释一下吗？
我的例子:

int numbers[15]{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
for (int i = 0; i < 5; i++) {
    for (int j = 0; j < 3; j++) {   
    }   
}

Answer 1

可以使用一个循环来完成。我认为，如果您查看了我的解决方案，则可以使用嵌套循环来实现。

double ans[10];
for(int i=0, j=0;i<15;i+=3, j++){
    double s=(double)(numbers[i]+numbers[i+1]+numbers[i+2])/2;
    double area = sqrt(s*(s-numbers[i])*(s-numbers[i+1])*(s-numbers[i+2]));
    ans[j]=area;
}
for(int i=0;i<5;i++) cout<<ans[i]<<endl;