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#include <iostream>
#include <vector>
using namespace std;

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

    vector<int> a(n);  // Tree visits (the trees visited on each day)
    for (int i = 0; i < n; ++i) {
        cin >> a[i];
    }

    // This will track how many leaves are eaten on each day
    vector<int> leaves(n, 0);  // Initialize with 0 leaves eaten each day

    // Apply modifications
    for (int i = 0; i < m; ++i) {
        int p, w;
        cin >> p >> w;
        // Apply the modification to the first p days
        for (int j = 0; j < p; ++j) {
            leaves[j] += w;
        }
    }

    // Build the prefix sum for the leaves eaten
    vector<vector<long long>> prefix_sum(1000006, vector<long long>(n + 1, 0));  // Max tree number is 10^6
    for (int i = 0; i < n; ++i) {
        // We accumulate leaves in prefix sum for each tree
        prefix_sum[a[i]][i+1] = leaves[i];
    }

    // Now compute the prefix sum for each tree
    for (int i = 0; i < 1000006; ++i) {
        for (int j = 1; j <= n; ++j) {
            prefix_sum[i][j] += prefix_sum[i][j-1];
        }
    }

    // Handle queries
    for (int i = 0; i < z; ++i) {
        int p, d;
        cin >> p >> d;

        // Output the answer for this query: total leaves eaten from tree d during the first p days
        cout << prefix_sum[d][p] << endl;
    }

    return 0;
}