22 lines
904 B
C++
22 lines
904 B
C++
/** Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be:
|
|
1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ...
|
|
By considering the terms in the Fibonacci sequence whose values do not exceed four million, find the sum of the even-valued terms. */
|
|
|
|
#include "0.hpp"
|
|
|
|
int main()
|
|
{
|
|
const uu _max = 4000000;
|
|
uu fib[3] = {0, 1, 1}; // 设置 fib 数列循环的数组
|
|
uu count = 1; // fib 数列的项计数器
|
|
uu sum = 0; // 满足条件的数的和
|
|
while(fib[count] <= _max) { // fib 数列小于要求值时不断循环
|
|
if(fib[count] % 2 == 0) sum += fib[count]; // 满足条件的项计入总和
|
|
//cout << fib[count] << endl;
|
|
count = (count + 1) % 3; // 项计数器
|
|
fib[count] = fib[(count + 1) % 3] + fib[(count + 2) % 3]; // fib 数列递推公式
|
|
}
|
|
cout << sum << endl; // 输出结果
|
|
return 0;
|
|
}
|