Missing Number In Array
123456789101112131415
let arra=[1,2,3,4,6]// 4 is missing, given n-1 aaray[i.e 3], range till 4
function findMissingNum(arr){
let n=arr.length+1;
let totalSum=0;
let actualArrSum=n*(n+1)/2;
for(let a=0;a<arr.length;a++){
totalSum=arr[a]+totalSum;
}
return actualArrSum-totalSum;
}
console.log('Missing Num',findMissingNum(arra));
JavaScript
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