50 lines
977 B
C++
50 lines
977 B
C++
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#include <bits/stdc++.h>
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using namespace std;
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/*
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浮点数不能太大，10000>=a>=-10000
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*/
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double sqrt(int n) {
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double x = n;
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for (int i = 1; i <= 100; i++) x = (x * x + n) / (2 * x);
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return x;
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}
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double sqrt3(int n) {
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double x = n;
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for (int i = 1; i <= 100; i++) x = (2 * x * x * x + n) / (3 * x * x);
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return x;
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}
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double sqrt4(int n) {
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double x = n;
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for (int i = 1; i <= 100; i++) x = (3 * x * x * x * x + n) / (4 * x * x * x);
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return x;
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}
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double sqrt5(int n) {
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double x = n;
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for (int i = 1; i <= 100; i++) x = (4 * x * x * x * x * x + n) / (5 * x * x * x * x);
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return x;
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}
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int main() {
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// 求n的平方根和立方根
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double n;
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cin >> n;
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// 平方根
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printf("%.6lf\n", sqrt(n));
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// 立方根
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printf("%.6lf\n", sqrt3(n));
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// 4次方根
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printf("%.6lf\n", sqrt4(n));
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// 5次方根
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printf("%.6lf\n", sqrt5(n));
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return 0;
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}
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