37 lines
744 B
Plaintext
37 lines
744 B
Plaintext
/* ===== 模块6：函数 =====
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* test18_recursion — 递归函数
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* 难度：3/5
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* 验证点：递归调用、多路递归、递归终止条件
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*/
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fn fib(n: i32) i32 {
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if n <= 1 { ret n; }
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ret fib(n - 1) + fib(n - 2);
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}
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fn fact(n: i32) i32 {
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if n <= 0 { ret 1; }
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ret n * fact(n - 1);
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}
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fn main() i32 {
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/* 斐波那契 */
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var f0 := fib(0);
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if f0 != 0 { ret 1; }
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var f1 := fib(1);
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if f1 != 1 { ret 2; }
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var f5 := fib(5);
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if f5 != 5 { ret 3; }
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var f10 := fib(10);
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if f10 != 55 { ret 4; }
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/* 阶乘 */
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var fact0 := fact(0);
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if fact0 != 1 { ret 5; }
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var fact3 := fact(3);
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if fact3 != 6 { ret 6; }
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var fact5 := fact(5);
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if fact5 != 120 { ret 7; }
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ret 0;
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}
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