#include 
    
     #include 
     
      #include 
      
       #include 
       
        using namespace std;const int maxn =  50000+10;inline long long read(){    long long k=0;    char c;    c=getchar();    while(!isdigit(c))c=getchar();    while(isdigit(c)){k=(k<<3)+(k<<1)+c-'0';c=getchar();}    return k;}long long n, m, bl, answer, curL = 1, curR = 0, cnt[maxn], a[maxn], gg;struct query{    long long p, l, r;}e[maxn];struct answers{    long long x, y;}ans[maxn], now;long long gcd(long long x, long long y){    if(x%y == 0) return y;    else return gcd(y,x%y);}bool cmp(query a, query b){    return (a.l/bl) == (b.l/bl) ? a.r < b.r : a.l < b.l;}void add(long long pos){    cnt[a[pos]]++;    if(cnt[a[pos]] > 1)     now.x = now.x + cnt[a[pos]]*(cnt[a[pos]]-1)-(cnt[a[pos]]-1)*(cnt[a[pos]]-2);}void remove(long long pos){    cnt[a[pos]]--;    if(cnt[a[pos]] > 0)     now.x = now.x + cnt[a[pos]]*(cnt[a[pos]]-1)-(cnt[a[pos]]+1)*cnt[a[pos]];}int main(){    n = read(); m = read();        bl = sqrt(n);        for(long long i = 1; i <= n; i++)    a[i] = read();        for(long long i = 1; i <= m; i++)    {        e[i].l = read(); e[i].r = read(); e[i].p = i;    }        sort(e+1,e+1+m,cmp);        for(long long i = 1; i <= m; i++)    {        long long L = e[i].l, R = e[i].r;        while(curL < L)             remove(curL++);        while(curL > L)            add(--curL);        while(curR < R)            add(++curR);        while(curR > R)            remove(curR--);        now.y = (e[i].r-e[i].l+1)*(e[i].r-e[i].l);        if (!now.x)         {            now.x=0;            now.y=1;            }        gg = gcd(now.x, now.y);        ans[e[i].p].x = now.x/gg;        ans[e[i].p].y = now.y/gg;    }    for(long long i = 1; i <= m; i++)    printf("%lld/%lld\n",ans[i].x,ans[i].y);    return 0;}