General PROG1092

#include<stdio.h>
int general[100010];

int find(int x){
    if(general[x] == x)return x;
    return general[x] = find(general[x]);
}
void unions(int x,int y){
    int gx = find(x);
    int gy = find(y);
    general[y] = gx;
}
bool isset(int x,int y){
    return find(x) == find(y);
}

int main()
{
    int n,m;
    scanf("%d %d",&n,&m);
    int soldiers[n+1];
    for(int i=1;i<=n;i++)scanf("%d",&soldiers[i]);
    for(int i=1;i<=n;i++)general[i] = i;

    for(int i=1;i<=m;i++){
        int x,y;
        scanf("%d %d",&x,&y);
        if(isset(x,y)){
            printf("-1\n");
            continue;
        }
        int gx = find(x);
        int gy = find(y);
        if(soldiers[gx] > soldiers[gy]){ // x win
            unions(gx,gy);
            soldiers[gx] += soldiers[gy]/2;
            printf("%d\n",gx);
        }
        else if(soldiers[gy] > soldiers[gx]){ // y win
            unions(gy,gx);
            soldiers[gy] += soldiers[gx]/2;
            printf("%d\n",gy);
        }
        else{
        //  printf("Test eq\n");
            if(gx < gy){ // x win
                unions(gx,gy);
                soldiers[gx] += soldiers[gy]/2;
                printf("%d\n",gx);
            }else{
                unions(gy,gx);
                soldiers[gy] += soldiers[gx]/2;
                printf("%d\n",gy);
            }
        }
    }
    return 0;
}