#include <iostream>

#include <cstdio>

#include <sstream>

#include <cstring>

#include <map>

#include <set>

#include <vector>

#include <stack>

#include <queue>

#include <algorithm>

#include <cmath>

#define rap(a, n) for(int i=a; i<=n; i++)

#define MOD 2018

#define LL long long

#define ULL unsigned long long

#define Pair pair<int, int>

#define mem(a, b) memset(a, b, sizeof(a))

#define _  ios_base::sync_with_stdio(0),cin.tie(0)

//freopen("1.txt", "r", stdin);

using namespace std;

const int maxn = ;

struct TwoSAT {

    int n;

    vector<int> G[maxn*];

    bool mark[maxn*];

    int S[maxn*], c;

    bool dfs(int x) {

        if (mark[x^]) return false;

        if (mark[x]) return true;

        mark[x] = true;

        S[c++] = x;

        for (int i = ; i < G[x].size(); i++)

            if (!dfs(G[x][i])) return false;

        return true;

    }

    void init(int n) {

        this->n = n;

        for (int i = ; i < n*; i++)

            G[i].clear();

        memset(mark, , sizeof(mark));

    }

    void add_clause(int x, int xval, int y, int yval) {

        x = x *  + xval;

        y = y *  + yval;

        G[x^].push_back(y);

        G[y^].push_back(x);

    }

    bool solve() {

        for(int i = ; i < n*; i += )

            if(!mark[i] && !mark[i+]) {

                c = ;

                if(!dfs(i)) {

                    while(c > ) mark[S[--c]] = false;

                    if(!dfs(i+)) return false;

                }

            }

        return true;

    }

};

TwoSAT solver;

int n, m, total_age, age[maxn];

int is_young(int x) {

    return age[x] * n < total_age;

}

int main() {

    while(scanf("%d%d", &n, &m) ==  && n) {

        total_age = ;

        for(int i = ; i < n; i++) {

            scanf("%d", &age[i]);

            total_age += age[i];

        }

        solver.init(n);

        for(int i = ; i < m; i++) {

            int a, b;

            scanf("%d%d", &a, &b);

            a--;

            b--;

            if(a == b) continue;

            solver.add_clause(a, , b, );   //不能同时为真

            if(is_young(a) == is_young(b))

                solver.add_clause(a, , b, );   //不能同时为假

        }

        if(!solver.solve()) printf("No solution.\n");

        else {

            for(int i = ; i < n; i++)

                if(solver.mark[i*]) printf("C\n");   //设的是选c为真  因为年龄小和年龄大的c是相同的  a和b不好直接判断 所以只要c被标记了 那么就是选了c

                else if(is_young(i)) printf("B\n");    //如果没选c  那就判断是不是年龄小的

                else printf("A\n");

        }

    }

    return ;

}