Safe average without overflow
Medium
Java
Data Types
23 views
Problem Statement
Task: return average of two ints without overflow.
Input Format
Two integers a and b.
Output Format
An integer: average of a and b without overflow.
Example
2147483647 2147483647
2147483647
Constraints
• a and b are valid integers
• Must avoid overflow
• Must avoid overflow
Concept Explanation
If we calculate (a + b) / 2, overflow may happen.
So we use a safe formula:
a + (b - a) / 2
This avoids adding two large numbers directly.
So we use a safe formula:
a + (b - a) / 2
This avoids adding two large numbers directly.
Step-by-Step Explanation
1.Read integers a and b.
2.Compute result = a + (b - a) / 2.
3.Return result.
2.Compute result = a + (b - a) / 2.
3.Return result.
Concept Explanation
If we calculate (a + b) / 2, overflow may happen.
So we use a safe formula:
a + (b - a) / 2
This avoids adding two large numbers directly.
So we use a safe formula:
a + (b - a) / 2
This avoids adding two large numbers directly.
Step-by-Step Explanation
1.Read integers a and b.
2.Compute result = a + (b - a) / 2.
3.Return result.
2.Compute result = a + (b - a) / 2.
3.Return result.
Input / Output Format
Input Format
Two integers a and b.
Output Format
An integer: average of a and b without overflow.
Constraints
• a and b are valid integers
• Must avoid overflow
• Must avoid overflow
Examples
Input:
2147483647 2147483647
Output:
2147483647
Example Solution (Public)
static int safeAvg(int a,int b){return (int)(((long)a+(long)b)/2); }
Official Solution Code
static int safeAvg(int a,int b){return (int)(((long)a+(long)b)/2); }
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