#include <cstdio>
#include <vector>
using std::vector;
using std::pair;
const int maxn = 1e5 + 5;
int n, m, x, y;
int a[maxn], b[maxn];
vector<pair<int, int>> v;
int main() {
    scanf("%d %d %d %d", &n, &m, &x, &y);
    for (int i = 1; i <= n; i++)
        scanf("%d", &a[i]);
    for (int i = 1; i <= m; i++)
        scanf("%d", &b[i]);
    for (int i = 1, j = 1; i <= n; i++) {
        for (; j <= m && a[i] - x > b[j]; j++);
        if (j > m)  break;
        if (a[i] + y >= b[j]) {
            v.push_back({i, j});
            j++;
        }
    }
    printf("%d\n", (int)v.size());
    for (auto i : v) {
        printf("%d %d\n", i.first, i.second);
    }
}原文:https://www.cnblogs.com/AlphaWA/p/10895693.html