41 lines
1021 B
C++
41 lines
1021 B
C++
#include <bits/stdc++.h>
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using namespace std;
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//高精度+裴波那契数列
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//本题目考点：
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//1、递推
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//2、递推关系式的推导：找出任意一个位置，思考它是怎么来的，再用加法原理。
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vector<int> add(vector<int> &A, vector<int> &B) {
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if (A.size() < B.size()) return add(B, A);
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vector<int> C;
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int t = 0;
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for (int i = 0; i < A.size(); i++) {
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t += A[i];
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if (i < B.size()) t += B[i];
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C.push_back(t % 10);
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t /= 10;
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}
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if (t) C.push_back(t);
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return C;
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}
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int main() {
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int m, n;
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cin >> m >> n;
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vector<int> A, B, C;
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A.push_back(1);
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B.push_back(1);
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for (int i = 3; i <= n - m + 1; i++) {
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C = add(A, B);
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//对加数需要重新赋值
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//A<---B
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A.assign(B.begin(), B.end());
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//B<---C
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B.assign(C.begin(), C.end());
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}
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//倒序输出结果
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for (int i = B.size() - 1; i >= 0; i--)printf("%d", B[i]);
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return 0;
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} |