26 lines
521 B
JavaScript
26 lines
521 B
JavaScript
function product_Range(a,b) {
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var prd = a,i = a;
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while (i++< b) {
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prd*=i;
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}
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return prd;
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}
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function combinations(n, r)
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{
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if (n==r)
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{
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return 1;
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}
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else
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{
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r=(r < n-r) ? n-r : r;
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return product_Range(r+1, n)/product_Range(1,n-r);
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}
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}
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console.log(combinations(6, 2));
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console.log(combinations(5, 3));
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