24 lines
349 B
C
24 lines
349 B
C
#include<stdio.h>
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int cnk(int n, int k) {
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int res = 1;
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for (int i=n-k+1; i<=n; ++i)
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res *= i;
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for (int i=2; i<=k; ++i)
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res /= i;
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return res;
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}
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int main(void)
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{
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int n, k;
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scanf("%d%d", &n,&k);
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//Input: 3 2 output: 3
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//Input: 30 10
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//output: -108
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printf("%d",cnk(n,k));
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return 0;
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}
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