以下代码执行后，数组 arr 的内容是（ ）int arr[6] = {1, 2, 3, 4, 5, 6}; for (int i = 0; i < 6; i += 2) { arr[i] = arr[i] + arr[i+1]; arr[i+1] = arr[i] - arr[i+1]; arr[i] = arr[i] - arr[i+1]; }
A. {2,1,4,3,6,5}
B. {1,2,3,4,5,6}
C. {3,1,4,2,5,3}
D. {1,3,2,5,4,6}
正确答案：A
试卷来源：202512 CCF-GESP编程能力等级认证C++三级真题