Someone please help me with this question. Stuck with it for weeks now

I am getting WA for CHRL4 problem. I have implemented an idea suggested in the editorial for the problem that should work for subtask1 but should time out for subtask2. Even that is not happening. I am just getting WA for all test cases.

Here is the link to the problem:

Here is the code:

#include<iostream>
#include<stdio.h>
#include<algorithm>
#include<string>
#include<string.h>
#include<math.h>
#include<set>
#include<vector>
#include<utility>

#define MOD 1000000007

using namespace std;


int main ( ) {

    long long  n, k, minipos, cost[100006], ans[100006];
    double mini, mi[100006];
    cin>>n>>k;

    for ( int i = 0; i < n; i++ ) {
        scanf("%lld", &cost[i]);
    }

    mi[0] = log(cost[0]);
    ans[0] = cost[0];

    for ( int i = 1; i < n; i++ ) {
        mini = -1;
        for ( int j = 1; ( ( j <= k ) && ( ( i - j ) >= 0 ) ); j++ ) {
            if( mini == -1 ) {
                mini = mi[i-j];
                minipos = i - j;
            }
            else if ( mini > mi[i-j] ) {
                mini = mi[i-j];
                minipos = i - j;
            }
        }
        mi[i] = mini + log(cost[i]);
        ans[i] = ( ( cost[minipos] % MOD ) * ( cost[i] % MOD ) ) % MOD;
    }
    cout<<ans[n-1];


    return 0;
}

Solved the issue. Error was in line
ans[i] = ( ( cost[minipos] MOD ) * ( cost[i] MOD ) ) MOD; changed it to: ans[i] = ( ( ans[minipos] MOD ) * ( cost[i] MOD ) ) MOD;

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