#include <bits/stdc++.h>

using namespace std;

long long D[100005], D2[100005];
pair<long long, long long> v[100005];
vector<long long> A, A2;
long long N, X, K;
long long solution;

int main(){

    cin >> N>> X >> K;
    for(int i = 1; i <= N; i ++)
    {
        cin >> v[i].first >> v[i].second;
        if(v[i].first < X)
            A.push_back(abs(v[i].first - X));
        else
             A2.push_back(abs(v[i].first - X));
    }
    sort(A.begin(), A.end());
    sort(A2.begin(), A2.end());
    sort(v + 1, v + N + 1);

    for(int i = N; i >= 1; i --)
    {
        if(v[i].first < X)
        D[i] += D[i + 1] + v[i].second;
    }

    int j = 1;
    while( v[j].first < X && j <= N)
    {
        if(X - v[j].first <= K)
        {
            solution += v[j].second;
        }
        j ++;
    }
    int j2 = j;
    while( v[j2].first > X && j2 <= N)
    {
        if(v[j2].first - X <= K)
        {
            D2[j2] += v[j2].second + D2[j2 - 1];
            solution = max(solution, D2[j2]);
        }
        j2 ++;
    }
    j2 --;

    for(int i = j; i <= N; i ++)
    {
        if(v[i].first > X && v[i].first - X <= K)
        {
            auto pos = upper_bound(A.begin(), A.end(), (K - 2 * abs(v[i].first - X) ) ) - A.begin();
            if(pos > 0)
                if(pos )
                solution = max(solution, D2[i] + D[j - pos]);
        }
    }

    for(int i = 1; i < j; i ++)
    {
        if(v[i].first < X && X - v[i].first <= K)
        {
            auto pos = upper_bound(A2.begin(), A2.end(), (K - 2 * abs(v[i].first - X) ) ) - A2.begin();
            if(pos > 0)
                solution = max(solution, D[i] + D2[j + pos - 1]);
        }
    }

    cout << solution;


    return 0;
}