DynamicProgrammingStriver/FrogJumpLecture3.cpp at main · dhruvkej9/DynamicProgrammingStriver · GitHub

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#include "vector"
#include <iostream>
#include <climits>
using namespace std;
int f(int ind,vector<int> &heights,vector<int> &dp)
{
    if(ind == 0)
    {
        return 0;
    }
    if(dp[ind] != -1) return dp[ind];
    int left = f(ind-1,heights,dp) + abs(heights[ind]-heights[ind-1]);
    int right = INT_MAX;
    if(ind > 1) right = f(ind-2,heights,dp) + abs(heights[ind]-heights[ind-2]);
    return dp[ind] = min(left,right);
}
int frogJump(int n, vector<int> &heights)
{
    vector<int> dp(n,-1);
    dp[0] = 0;
    for(int i=1;i<n;i++)
    {
        int fs = dp[i-1] + abs(heights[i]-heights[i-1]);
        int ss = INT_MAX;
        if(i > 1)
        {
            ss = dp[i-2] + abs(heights[i] - heights[i-2]);
        }
        dp[i] = min(fs,ss);
    }
    return dp[n-1];
}
int frogJump(int n, vector<int> &heights)
{
    int prev = 0;
    int prev2 = 0;
    for(int i=1;i<n;i++)
    {
        int fs = prev + abs(heights[i]-heights[i-1]);
        int ss = INT_MAX;
        if(i > 1)
        {
            ss = prev2 + abs(heights[i] - heights[i-2]);
        }
        int curi = min(fs,ss);
        prev2 = prev;
        prev = curi;
    }
    return prev;
}