import com.sun.source.tree.Tree;

import java.io.*;
import java.math.BigInteger;
import java.util.*;
import java.util.function.BiFunction;
import java.util.function.BinaryOperator;
import java.util.function.IntUnaryOperator;
import java.util.function.LongUnaryOperator;
import java.util.stream.Collectors;

public class Main {
    static In in = new FastIn();
    static Out out = new Out(false);
    static final long inf = 0x1fffffffffffffffL;
    static final int iinf = 0x3fffffff;
    static final double eps = 1e-9;
    static long mod = 998244353;

    int n = in.nextInt();
    int m = in.nextInt();
    int qq = in.nextInt();
    int[] a = in.nextIntArray(n);
    E[] b = new E[m];
    List<List<E>> e = new ArrayList<>();

    void solve() {
        for (int i = 0; i < n; i++) {
            e.add(new ArrayList<>());
        }
        E[] es = new E[m];
        for (int i = 0; i < m; i++) {
            es[i] = new E(-1,-1,inf);
        }
        for (int i = 0; i < m; i++) {
            int u = in.nextInt()-1;
            int v = in.nextInt()-1;
            long w = in.nextLong();
            b[i] = new E(u,v,w);
            e.get(u).add(new E(u,v,w));
            e.get(v).add(new E(v,u,w));
        }
        E[] query = new E[qq];
        for (int i = 0; i < qq; i++) {
            int ss = in.nextInt()-1;
            int cc = in.nextInt();
            query[i] = new E(ss,i,cc);
        }

        Arrays.sort(b);
        UnionFind uf = new UnionFind(n,query);
        for (int i = 0; i < m; i++) {
            uf.unite(b[i].u,b[i].v,b[i].w);
        }
        for (int i = 0; i < qq; i++) {
            out.println(uf.ans[i]);
        }
    }



    public static void main(String... args) {
        new Main().solve();
        out.flush();
    }
}

class E implements Comparable<E>{
    public int u;
    public int v;
    public long w;

    public E(int u,int v,long w){
        this.u = u;
        this.v = v;
        this.w = w;
    }

    @Override
    public int compareTo(E o) {
        return Long.compare(w,o.w);
    }
}

class UnionFind{

    int n;
    int m;
    int[] parent;
    int[] size;

    List<PriorityQueue<E>> pqs = new ArrayList<>();
    E[] query;
    long[] ans;

    UnionFind(int n,E[] query){
        parent = new int[n];
        size = new int[n];
        for (int i = 0; i < n; i++) {
            parent[i] = i;
            size[i] = 1;
        }
        this.n = n;
        m = n;
        this.query = query;
        ans = new long[n];
        for (int i = 0; i < n; i++) {
            pqs.add(new PriorityQueue<>());
        }
        for (E e : query) {
            pqs.get(e.u).add(e);
        }
    }

    public int root(int x){
        while (parent[x] != x){
            x = parent[x] = parent[parent[x]];
        }
        return x;
    }

    public boolean unite(int x,int y,long cost){
        x = root(x);
        y = root(y);
        if(x == y)return false;
        if(size[x] > size[y]){
            parent[y] = x;
            size[x] += size[y];
            pqs.get(x).addAll(pqs.get(y));
            while(!pqs.get(x).isEmpty() && pqs.get(x).peek().w <= size[x]){
                ans[pqs.get(x).poll().v] = cost;
            }
        }else{
            parent[x] = y;
            size[y] += size[x];
            pqs.get(y).addAll(pqs.get(x));
            while(!pqs.get(y).isEmpty() && pqs.get(y).peek().w <= size[y]){
                ans[pqs.get(y).poll().v] = cost;
            }
        }
        m--;
        return true;
    }

    @Override
    public String toString(){
        List<StringJoiner> list = new ArrayList<>();
        for (int i = 0; i < m; i++) {
            list.add(new StringJoiner(" "));
        }
        int[] p = new int[n];
        Arrays.fill(p,m);
        int l = 0;
        for (int i = 0; i < m; i++) {
            if(p[root(i)] == m){
                p[root(i)] = l;
                l++;
            }
            list.get(p[root(i)]).add(i+"");
        }
        StringBuilder s = new StringBuilder();
        for (int i = 0; i < m; i++) {
            s.append(list.get(i));
        }
        return s.toString();
    }
}

class FastIn extends In {
    private final BufferedInputStream reader = new BufferedInputStream(System.in);
    private final byte[] buffer = new byte[0x10000];
    private int i = 0;
    private int length = 0;

    public int read() {
        if (i == length) {
            i = 0;
            try {
                length = reader.read(buffer);
            } catch (IOException ignored) {
            }
            if (length == -1) {
                return 0;
            }
        }
        if (length <= i) {
            throw new RuntimeException();
        }
        return buffer[i++];
    }

    String next() {
        StringBuilder builder = new StringBuilder();
        int b = read();
        while (b < '!' || '~' < b) {
            b = read();
        }
        while ('!' <= b && b <= '~') {
            builder.appendCodePoint(b);
            b = read();
        }
        return builder.toString();
    }

    String nextLine() {
        StringBuilder builder = new StringBuilder();
        int b = read();
        while (b != 0 && b != '\r' && b != '\n') {
            builder.appendCodePoint(b);
            b = read();
        }
        if (b == '\r') {
            read();
        }
        return builder.toString();
    }

    int nextInt() {
        long val = nextLong();
        if ((int) val != val) {
            throw new NumberFormatException();
        }
        return (int) val;
    }

    long nextLong() {
        int b = read();
        while (b < '!' || '~' < b) {
            b = read();
        }
        boolean neg = false;
        if (b == '-') {
            neg = true;
            b = read();
        }
        long n = 0;
        int c = 0;
        while ('0' <= b && b <= '9') {
            n = n * 10 + b - '0';
            b = read();
            c++;
        }
        if (c == 0 || c >= 2 && n == 0) {
            throw new NumberFormatException();
        }
        return neg ? -n : n;
    }
}

class In {
    private final BufferedReader reader = new BufferedReader(new InputStreamReader(System.in), 0x10000);
    private StringTokenizer tokenizer;

    String next() {
        try {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                tokenizer = new StringTokenizer(reader.readLine());
            }
        } catch (IOException ignored) {
        }
        return tokenizer.nextToken();
    }

    int nextInt() {
        return Integer.parseInt(next());
    }

    long nextLong() {
        return Long.parseLong(next());
    }

    double nextDouble() {
        return Double.parseDouble(next());
    }

    char[] nextCharArray() {
        return next().toCharArray();
    }

    String[] nextStringArray(int n) {
        String[] s = new String[n];
        for (int i = 0; i < n; i++) {
            s[i] = next();
        }
        return s;
    }

    char[][] nextCharGrid(int n, int m) {
        char[][] a = new char[n][m];
        for (int i = 0; i < n; i++) {
            a[i] = next().toCharArray();
        }
        return a;
    }

    int[] nextIntArray(int n) {
        int[] a = new int[n];
        for (int i = 0; i < n; i++) {
            a[i] = nextInt();
        }
        return a;
    }

    int[] nextIntArray(int n, IntUnaryOperator op) {
        int[] a = new int[n];
        for (int i = 0; i < n; i++) {
            a[i] = op.applyAsInt(nextInt());
        }
        return a;
    }

    int[][] nextIntMatrix(int h, int w) {
        int[][] a = new int[h][w];
        for (int i = 0; i < h; i++) {
            a[i] = nextIntArray(w);
        }
        return a;
    }

    long[] nextLongArray(int n) {
        long[] a = new long[n];
        for (int i = 0; i < n; i++) {
            a[i] = nextLong();
        }
        return a;
    }

    long[] nextLongArray(int n, LongUnaryOperator op) {
        long[] a = new long[n];
        for (int i = 0; i < n; i++) {
            a[i] = op.applyAsLong(nextLong());
        }
        return a;
    }

    long[][] nextLongMatrix(int h, int w) {
        long[][] a = new long[h][w];
        for (int i = 0; i < h; i++) {
            a[i] = nextLongArray(w);
        }
        return a;
    }

    List<List<Integer>> nextEdges(int n, int m, boolean directed) {
        List<List<Integer>> res = new ArrayList<>();
        for (int i = 0; i < n; i++) {
            res.add(new ArrayList<>());
        }
        for (int i = 0; i < m; i++) {
            int u = nextInt() - 1;
            int v = nextInt() - 1;
            res.get(u).add(v);
            if (!directed) {
                res.get(v).add(u);
            }
        }
        return res;
    }
}

class Out {
    private final PrintWriter out = new PrintWriter(System.out);
    private final PrintWriter err = new PrintWriter(System.err);
    boolean autoFlush = false;
    boolean enableDebug;

    Out(boolean enableDebug) {
        this.enableDebug = enableDebug;
    }

    void println(Object... args) {
        if (args == null || args.getClass() != Object[].class) {
            args = new Object[]{args};
        }
        out.println(Arrays.stream(args).map(obj -> {
            Class<?> clazz = obj == null ? null : obj.getClass();
            return clazz == Double.class ? String.format("%.10f", obj) :
                    clazz == byte[].class ? Arrays.toString((byte[]) obj) :
                            clazz == short[].class ? Arrays.toString((short[]) obj) :
                                    clazz == int[].class ? Arrays.toString((int[]) obj) :
                                            clazz == long[].class ? Arrays.toString((long[]) obj) :
                                                    clazz == char[].class ? Arrays.toString((char[]) obj) :
                                                            clazz == float[].class ? Arrays.toString((float[]) obj) :
                                                                    clazz == double[].class ? Arrays.toString((double[]) obj) :
                                                                            clazz == boolean[].class ? Arrays.toString((boolean[]) obj) :
                                                                                    obj instanceof Object[] ? Arrays.deepToString((Object[]) obj) :
                                                                                            String.valueOf(obj);
        }).collect(Collectors.joining(" ")));
        if (autoFlush) {
            out.flush();
        }
    }

    void debug(Object... args) {
        if (!enableDebug) {
            return;
        }
        if (args == null || args.getClass() != Object[].class) {
            args = new Object[]{args};
        }
        err.println(Arrays.stream(args).map(obj -> {
            Class<?> clazz = obj == null ? null : obj.getClass();
            return clazz == Double.class ? String.format("%.10f", obj) :
                    clazz == byte[].class ? Arrays.toString((byte[]) obj) :
                            clazz == short[].class ? Arrays.toString((short[]) obj) :
                                    clazz == int[].class ? Arrays.toString((int[]) obj) :
                                            clazz == long[].class ? Arrays.toString((long[]) obj) :
                                                    clazz == char[].class ? Arrays.toString((char[]) obj) :
                                                            clazz == float[].class ? Arrays.toString((float[]) obj) :
                                                                    clazz == double[].class ? Arrays.toString((double[]) obj) :
                                                                            clazz == boolean[].class ? Arrays.toString((boolean[]) obj) :
                                                                                    obj instanceof Object[] ? Arrays.deepToString((Object[]) obj) :
                                                                                            String.valueOf(obj);
        }).collect(Collectors.joining(" ")));
        err.flush();
    }

    void println(int a) {
        out.println(a);
        if (autoFlush) {
            out.flush();
        }
    }

    void println(long a) {
        out.println(a);
        if (autoFlush) {
            out.flush();
        }
    }

    void println(double a) {
        out.println(String.format("%.10f", a));
        if (autoFlush) {
            out.flush();
        }
    }

    void println(String s) {
        out.println(s);
        if (autoFlush) {
            out.flush();
        }
    }

    void println(char[] s) {
        out.println(String.valueOf(s));
        if (autoFlush) {
            out.flush();
        }
    }

    void println(int[] a) {
        StringJoiner joiner = new StringJoiner(" ");
        for (int i : a) {
            joiner.add(Integer.toString(i));
        }
        out.println(joiner);
        if (autoFlush) {
            out.flush();
        }
    }

    void println(long[] a) {
        StringJoiner joiner = new StringJoiner(" ");
        for (long i : a) {
            joiner.add(Long.toString(i));
        }
        out.println(joiner);
        if (autoFlush) {
            out.flush();
        }
    }

    void flush() {
        err.flush();
        out.flush();
    }
}