/*Olá professora!
A operação da matriz e do código parar calcular o determinante através do método de Laplace será feita através do 
espaço para input ao lado (STDIN).
Comece substituindo a linha 1 do STDIN pelo tamanho da matriz (2 para 2x2 ou 3 para 3x3);
Em seguida, substitua a linha logo abaixo pelos valores da matriz, todos na mesma linha, separados somente por espaço.
*/


#include <stdio.h>

int determinante2x2 (int matriz[2][2]) {
    int diag1 = matriz[0][0] * matriz[1][1];
    int diag2 = matriz[0][1] * matriz[1][0];
    int resultado = diag1 - diag2;
    return resultado;
}

int determinante3x3(int matriz[3][3]) {
    int det = 0;

    for (int j = 0; j < 3; j++) {
        int submatriz[2][2];
        int linha_sub = 0;

        for (int i = 1; i < 3; i++) {
            int coluna_sub = 0;
            for (int k = 0; k < 3; k++) {
                if (k == j)
                    continue;
                submatriz[linha_sub][coluna_sub] = matriz[i][k];
                coluna_sub++;
            }
            linha_sub++;
        }

        int sinal = (j % 2 == 0) ? 1 : -1;
        det += sinal * matriz[0][j] * determinante2x2(submatriz);
    }

    return det;
}

int main(){
    int tipo;

    printf("Digite o tamanho de sua matriz. ""2"", para 2x2, ou ""3"" para 3x3: \n");
    scanf("%d", &tipo);
    if (tipo == 2) {
        int matriz[2][2], resultadodet;
        printf("Digite os elementos da sua matriz 2x2: \n");
        for(int i=0; i<2; i++)
            for(int j=0; j<2; j++)
            scanf("%d", &matriz[i][j]);

    resultadodet = determinante2x2(matriz);
    printf("O determinante de sua matriz 2x2 e = %d", resultadodet);
    } else if (tipo == 3){
        int matriz[3][3], resultadodet;
        printf("Digite os elementos da sua matriz 3x3: \n");
        for(int i=0; i<3; i++)
            for(int j=0; j<3; j++)
            scanf("%d", &matriz[i][j]);

    resultadodet = determinante3x3(matriz);
    printf("O determinante de sua matriz 3x3 e = %d", resultadodet);
    } else {
        printf("Opção inválida, tchau!");
    }

    return 0;
}
by

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#include <stdio.h>
int main()
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    char name[50];
    printf("Enter name:");
    scanf("%s", name);
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    return 0;
    
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About C

C language is one of the most popular general-purpose programming language developed by Dennis Ritchie at Bell laboratories for UNIX operating system. The initial release of C Language was in the year 1972. Most of the desktop operating systems are written in C Language.

Key features:

  • Structured Programming
  • Popular system programming language
  • UNIX, MySQL and Oracle are completely written in C.
  • Supports variety of platforms
  • Efficient and also handle low-level activities.
  • As fast as assembly language and hence used as system development language.

Syntax help

Loops

1. If-Else:

When ever you want to perform a set of operations based on a condition if-else is used.

if(conditional-expression) {
   // code
} else {
   // code
}

You can also use if-else for nested Ifs and if-else-if ladder when multiple conditions are to be performed on a single variable.

2. Switch:

Switch is an alternative to if-else-if ladder.

switch(conditional-expression) {    
case value1:    
 // code    
 break;  // optional  
case value2:    
 // code    
 break;  // optional  
...    
    
default:     
 // code to be executed when all the above cases are not matched;    
}

3. For:

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement){  
  // code  
}

4. While:

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.

while(condition) {  
 // code 
}

5. Do-While:

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {
  // code 
} while (condition);

Arrays

Array is a collection of similar data which is stored in continuous memory addresses. Array values can be fetched using index. Index starts from 0 to size-1.

Syntax

One dimentional Array:

data-type array-name[size];

Two dimensional array:

data-type array-name[size][size];

Functions

Function is a sub-routine which contains set of statements. Usually functions are written when multiple calls are required to same set of statements which increases re-usuability and modularity.

Two types of functions are present in C

  1. Library Functions:

Library functions are the in-built functions which are declared in header files like printf(),scanf(),puts(),gets() etc.,

  1. User defined functions:

User defined functions are the ones which are written by the programmer based on the requirement.

How to declare a Function

return_type function_name(parameters);

How to call a Function

function_name (parameters)

How to define a Function

return_type function_name(parameters) {  
  //code
}