What is the problem with my approach?

[chhabrapiyush480 (Piyush Chhabra)]

Coding Blocks IDE

in this code,tot[i] represents total petrol needed to reach the end from the ith checkpoint and dp provides answer.

[O17LPOLA020023 (Abhijeet Jha)]

you are not considering all cases
eg for the test case
2 5 1 100
1 2 30 400
your code output is 442 (2 * 1+5 * 2+1 * 430)
but output should be
436 (2 * (1+2)+1 * 430)

I hope you got my point if you want to try another approach you can refer

Deepak_And_Journey

The approach you are following in your code seems incorrect, the correct approach is that you need to maintain an array suppose long long int M[100001], and then you will traverse the array elements and then check, if(i==0) { M[i]=cost[i]; } else { M[i]=min(M[i-1],cost[i]); } } And then u will initiliase : long long int final_cost=0; such that final_cost=final_cost+ petrol[i]*M[i]; The final _cost will determine your final answer.

In case of any doubt feel free to ask
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