mirror of
https://github.com/Kiritow/OJ-Problems-Source.git
synced 2024-03-22 13:11:29 +08:00
50 lines
1.0 KiB
C++
50 lines
1.0 KiB
C++
#include <iostream>
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using namespace std;
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__int64 p[21][21];
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__int64 gcd(__int64 a, __int64 b)
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{
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return b ? gcd(b, a % b) : a;
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}
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void init()
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{
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int i, j;
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for (i = 0; i <= 20; ++i)
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{
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p[i][0] = 1;
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p[i][i] = 0;
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}
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for (i = 2; i <= 20; ++i)
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for (j = 1; j < i; ++j)
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p[i][j] = p[i - 1][j] + p[i - 1][j - 1] * (i - 1);
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}
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void solve(int s, int n)
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{
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__int64 sum = 0, total = 0 , g;
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int i;
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for (i = 0; i < s; ++i)
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sum += p[n][i];
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total = sum;
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for ( ; i < n; ++i)
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total += p[n][i];
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g = gcd(sum, total);
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sum /= g;
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total /= g;
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if (total == 1 && sum == 1)
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printf("1\n");
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else if (sum == 0)
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printf("0\n");
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else printf("%I64d/%I64d\n", sum, total);
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}
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int main()
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{
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init();
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int tcase, w, h, n, s;
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scanf("%d", &tcase);
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while (tcase--)
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{
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scanf("%d%d%d", &w, &h, &s);
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solve(s, w * h);
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}
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return 0;
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}
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