Permutation and combination calculator

The permutation and combination calculator is a mathematical tool software focused on solving permutation and combination problems. The software interface is simple and intuitive, with low operating threshold. It is suitable for students, educators, data analysts, programmers and other groups.

Software features

Efficient and accurate calculation

Supports large number operations (such as calculating C(50,10)) to ensure accuracy of results.

Provides quick call of factorial function (n!) to simplify input of complex formulas.

Calculate and display results in real time to avoid manual calculation errors.

Flexible switching between multiple modes

Arrangement mode: considers the order of elements and is suitable for password generation, sequence design and other scenarios.

Combination mode: Ignore the order, suitable for lottery analysis, team selection and other scenarios.

Repeating element support: allows numbers or characters to be reused, expanding the scope of applications.

Visualization and interaction optimization

Display the results in the form of charts or lists, and visually present the combination distribution (such as the triangular distribution diagram of C(n,2)).

Supports result grouping, sorting and filtering to quickly locate target data.

Core functions

Basic computing functions

Permutation calculation: input n and r, calculate P(n,r)=n!/(n-r)!.

Example: The number of permutations of 3 letters selected from 5 letters is P(5,3)=60.

Combination calculation: input n and r, calculate C(n,r)=n!/[r!(n-r)!].

Example: Choose the number of combinations of 4 out of 10 numbers C(10,4)=210.

Advanced computing capabilities

Repeatable arrangement/combination: Supports repeated use of elements. For example, the number of arrangements for selecting 2 (repeatable) colors from 3 colors is 3²=9.

Probability calculation: Calculate the probability of an event by combining the permutation and combination results.

Example: Calculate the probability of drawing 5 straight flush cards from 52 cards (need to combine the number of combinations and card type rules).

Batch calculation: input multiple sets of (n, r) values ​​and generate a list of permutations or combinations at once.

Data management and export

History record: automatically saves the calculation process and supports review and reuse.

Result export: supports text, Excel and other formats to facilitate subsequent analysis.

FAQ

No results generated

Reason: Incorrect input parameters (such as r>n), duplicate elements or no boundary conditions are set.

Solution: Check the input range to ensure n≥r and the elements are unique; clarify whether duplication is allowed.

Slow performance

Reason: Generating a large number of permutations and combinations (such as C(20,10)=184,756 types) causes the calculation to time out.

Solution: Limit the number of results or simplify the input range; use parallel computing mode to speed up.

1. Optimized some functions

2. Solved many intolerable bugs