Hackerrank_Array_Manipulation_pre_computation.cpp

#include<bits/stdc++.h>
using namespace std;

const int N = 1e7 + 10;
long long int arr[N]; 

int main(){
    int n, m; cin >> n >> m;

    while(m--){
        int a, b, k; cin >> a >> b >> k;
        arr[a] += k;
        arr[b+1] -= k;
    }

    long long int mx = -1;
    for(int i=1; i<=n; i++){
        arr[i] = arr[i-1] + arr[i];
        mx = max(mx, arr[i]);
    }

    cout << mx << endl;
}