21 lines
336 B
C
21 lines
336 B
C
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#include<stdio.h>
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int cnk2(int n, int k) {
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double res = 1;
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for (int i=1; i<=k; ++i)
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res = res * (n-k+i) / i;
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return (int) (res + 0.01);
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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: 30045015
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printf("%d",cnk2(n,k));
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return 0;
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}
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