Help me out in this problem

#1


#2

hello @shivammishra20121999
pls wait i m checking

#3

c is indicating what step u have taken before right?

#4

@aman212yadav i am taking for the state to keep track the backward step

#5

@aman212yadav are u there ?

#6

yeah bro ,pls wait. will ping u back once it get resolved

#7

@shivammishra20121999
u solution looks correct.
one mistake that is there is u r not clearing ur map, so it will store answer of ur previous result.
also i believe this test case is wrong .
we cannot reach to 2000 from 0 using a->1999,b->2000 and forbidden state as [1998]
[1998]
1999
2000
2000

#8

@aman212yadav dude i am using map to store forbidden point so there is no need to clear it?

#9

i know it is storing forbidden state.
let say
obj x=solution(); // made object of ur solutiuon class.

x.minjumps(passed on set of tes case) ; // it will give some entries in ur map right?

x.minjumps(passed another set of test case) ; // note becuase it is same object it will be holding ur previous forbidden state right?
thats why i was telling u to clear ur map

#10

@aman212yadav i think you didnot understand my logic then aman you have read the question?

#11

@aman212yadav give me your number ?

#12

i have understood each bit of ur logic.

from i u have two options .
solve(i,c)-> min(1+solve(i+a,0) , 1+solve(i-b,c+1) );

base cases
if u reached to visited state or forbidden state u return big number
if u i<0 or i>4000 u return big numberm(indicates out of range)
if c>=2 that indicates u have take more than 1 backwar steps so u returned big number .

evrything is correct in ur logic.

one thing that might be creating an issue is ur search range
try increasinf ur range from 4000 to some big number.
it will work i guess

#13

@aman212yadav even it is not working ?

#14

wait bro , give me sometime will try to resolve it asap
till then try another problem

#15

@aman212yadav okay brother

#16

@shivammishra20121999

pls check ur updated code here->

    unordered_map<int,int>mp;

class Solution {
public:
    int dp[8005][2];//increased size
    int fun(int i, int c,int a, int b, int x)
    {
        // base condition 
        if(i<0 or i>8000 or c>=2 or mp.find(i)!=mp.end())return 1e9+1;// increased search domain
        
        if(i==x)return 0;
        if(dp[i][c]!=-1)
            return dp[i][c];
        
        dp[i][c]=1+fun(i+a,0,a,b,x);
        dp[i][c]=min(dp[i][c],1+fun(i-b,c+1,a,b,x));
        
        return dp[i][c];
    }
    int minimumJumps(vector<int>& forbidden, int a, int b, int x) { 
        mp.clear();//added
        for(int i=0;i<forbidden.size();i++)
            mp[forbidden[i]]=1;
        memset(dp,-1,sizeof(dp));
        
        int res=fun(0,0,a,b,x);
        if(res>=1e9)return -1;
        return res;
    }
};

basically i just changed ur search space from 4000 , i changed it to 8000 (no logic behind this number just a random guess)

rest evrything was correct

#17

@aman212yadav donot expect this from leetcode i think there is some fault in the checker code

#18

now it is working bro.
pls try to submit