Počítání Párů v Poli, což v danou částku
<script>
// javascript implementation of simple method to find count of
// pairs with given sum.
// Returns number of pairs in arr[0..n-1] with sum equal
// to 'sum'
function getPairsCount(arr , n , k) {
var m = new Map();
var count = 0;
for (var i = 0; i < n; i++) {
if (m.has(k - arr[i])) {
count += m.get(k - arr[i]);
}
if (m.has(arr[i])) {
m.set(arr[i], m.get(arr[i]) + 1);
} else {
m.set(arr[i], 1);
}
}
return count;
}
// Driver function to test the above function
var arr = [ 1, 5, 7, -1, 5 ];
var n = arr.length;
var sum = 6;
document.write("Count of pairs is " + getPairsCount(arr, n, sum));
// This code is contributed by umadevi9616
</script>
najít pár prvků z pole, jejichž součet se rovná dané číslo python
#Given an array of integers and a number, write a function that finds two elements from the array whose sum is equal to the given number.
def find_pair(arr, num):
for i in range(len(arr)):
for j in range(i + 1, len(arr)):
if arr[i] + arr[j] == num:
return [arr[i], arr[j]]
print(find_pair([3, 6, 8, -8, 10, 8], 16))
[6, 10]