Minimum Value to Get Positive Step by Step Sum
A easy-tier problem at 65% community acceptance, tagged with Array, Prefix Sum. Reported in interviews at Swiggy and 0 others.
You're given an array of integers and need to find the minimum starting value such that the running sum never drops below 1. It's an easy problem by LeetCode's metric, with a 64% acceptance rate, but it shows up in Swiggy assessments and others where prefix-sum logic matters. The trap is overthinking it. The actual solution is almost embarrassingly simple once you see it, but if you blank on the pattern during a live OA, StealthCoder surfaces the answer in seconds invisible to the proctor.
Companies that ask "Minimum Value to Get Positive Step by Step Sum"
Minimum Value to Get Positive Step by Step Sum is the kind of problem that decides whether you pass. StealthCoder reads the problem on screen and surfaces a working solution in under 2 seconds. Invisible to screen share. The proctor sees nothing. Built by a senior engineer who knows the OA is theater. This is the script.
Get StealthCoderThe key insight is that you don't iterate forward tracking sums. You iterate backward through the array, keeping a running minimum of what the prefix sum hits at each point. The minimum starting value is simply 1 minus the lowest prefix sum you encounter. Most candidates waste time building forward prefix sums or trying dynamic approaches when the backward scan solves it in one pass. The common miss: thinking you need to check each starting value individually. The actual pattern: compute the cumulative minimum and extract the answer directly. If this problem lands in your live assessment and you're blanking on whether to go forward or backward, StealthCoder runs invisibly during screen share and gives you the exact approach.
Pattern tags
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Minimum Value to Get Positive Step by Step Sum recycles across companies for a reason. It's easy-tier, and most candidates blank under the timer. StealthCoder is the hedge: an AI overlay invisible during screen share. It reads the problem and surfaces a working solution in under 2 seconds. Built by a senior engineer who knows the OA is theater. This is the script. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Minimum Value to Get Positive Step by Step Sum interview FAQ
Is this actually easy or is the acceptance rate misleading?+
The 64% acceptance rate is genuinely reflective. It's easy once you know the backward-scan pattern. The difficulty comes from second-guessing yourself and trying forward iteration first. Most people who fail are overthinking, not misunderstanding the problem.
How does Prefix Sum apply here?+
You track the cumulative sum as you move through the array. The trick is doing it in reverse: find the minimum cumulative sum you'd hit, then subtract it from 1. That's your starting value. Forward and backward prefix sums are both valid; backward is cleaner for this problem.
What's the worst mistake candidates make on this problem?+
Building a forward prefix sum array, then trying to binary search or iterate to find the answer. You don't need extra space or loops. A single backward pass and one integer gives you the result. It's greedy, not search.
Does Swiggy ask this a lot or was it a one-off?+
Swiggy is the only reported company in the data, but that doesn't mean it's rare overall. Array and prefix-sum combos are standard at most tech companies. This specific problem is bread-and-butter material, not a curveball.
How long should I spend on this during an OA?+
If you see the backward-scan pattern, you code it in 3 to 5 minutes. If you're stuck after 8 minutes, you're probably trying the wrong direction. That's when you pause, reset, and think about the problem from the end instead of the start.
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