Getting tle on spoj Audition.Here is my submission link, Pls help.
Here is the heart of the code:
map <ll,ll> mp;
mp.clear();
mp[0]++;
ll sum=0,n,k,ans=0;
cin>>n>>k;
ll a[n];
string str;
cin>>str;
for(ll i=0;i<n;i++)
{
a[i] = str[i] - (ll)'a' + 49;
sum +=a[i];
ans +=mp[sum-k];
mp[sum]++;
}