29 lines
647 B
C++
29 lines
647 B
C++
#include <bits/stdc++.h>
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using namespace std;
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int n, r;
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void dfs(int step, vector<int> path, int m) {
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//过不了就减减枝吧,剩下的不够了，就别再继续了。
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if (r - m > n - step) return;
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if (step == n + 1) return;
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if (m == r) {
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for (int i = 0; i < r; i++) printf("%3d", path[i]);
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printf("\n");
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return;
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}
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//下一个数字选择上
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vector<int> p1 = path;
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p1.push_back(step + 1);
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dfs(step + 1, p1, m + 1);
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//下一个数字放弃掉
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dfs(step + 1, path, m);
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}
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int main() {
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scanf("%d%d", &n, &r);
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dfs(0, {}, 0);
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return 0;
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} |