27 lines
450 B
C
27 lines
450 B
C
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#include<stdio.h>
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int cnk3(int n, int k)
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{
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const int maxn = n;
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int C[maxn+1][maxn+1];
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for (int i=0; i<=maxn; ++i)
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{
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C[i][0] = C[i][i] = 1;
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for (int j=1; j<i; ++j)
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C[i][j] = C[i-1][j-1] + C[i-1][j];
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}
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return C[n][k];
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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",cnk3(n,k));
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return 0;
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}
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