We have two sets of ranges; one is a single range of any length (R1) and the other is a set of ranges (R2) some or parts of which may or may not lie within the single range (R1).
We need to calculate the sum of the ranges in (R2) - whole or partial - that lie within the single range (R1).
const R1 = [20,40]; const R2 = [[14,22],[24,27],[31,35],[38,56]];
Result
= 2+3+4+2 = 11
R1 = [120,356]; R2 = [[234,567]];
Result
122
Example
Let us write the code −
const R1 = [20,40]; const R2 = [[14,22],[24,27],[31,35],[38,56]]; const R3 = [120,356]; const R4 = [[234,567]]; function sumRanges(range, values) { const [start, end] = range; const res = values.reduce((acc, val) => { const [left, right] = val; const ex1 = Math.min(right, end); const ex2 = Math.max(left, start); const diff = ex1 - ex2; return acc + Math.max(0, diff); }, 0); return res; }; console.log(sumRanges(R1, R2)); console.log(sumRanges(R3, R4));
Output
And the output in the console will be −
11 122