 递归 int Fibon1(int n) { if (n == 1 || n == 2) { return 1; } else { return Fibon1(n - 1) + Fibon1(n - 2); } } int main() { int n = 0; int ret = 0; scanf("%d", &n); ret = Fibon1(n); printf("ret=%d", ret); return 0; }  非递归 int Fibno2(int n) { int num1 = 1; int num2 = 1; int tmp = 0; int i = 0; if (n < 3) { return 1; } else { for (i = 0; i>n-3; i++) { tmp = num1 + num2; num1 = num2; num2 = tmp; } return tmp; } }