SNCA:C

#include <stdio.h>

int main() {
    printf("Hello world\n");
    return 0;
}

This demonstrates an out-of-bounds access, which causes a segmentation fault. Segmentation faults refer to illegal accessing of memory that a program does not have access to.

The "soy" string (in C, a string is char[] or array of char) is of length 6, and thus valid indices are 0 to 5. The for loop basically goes past that and starts reading other variables in memory. Some compilers don't like it, but it works on MSVC420 portable.

#include <stdio.h>

int main() {
    char soy[] = "o algo";

    for (int c = -1024; c < 1024; c++) {
        printf("%c", soy[c]);
    }

    return 0;
}

This demonstrates a memory leak.

Here some memory is allocated, but never freed. An int[] is allocated with malloc() but free() is never called. If the pointer to that allocated memory is removed (such as popping off the call stack) then the block of memory essentially cannot be freed, causing a leak.

#include <stdlib.h>

void performUselessAllocation(size_t n) {
    // allocation called
    int* a = (int*)malloc(n * sizeof(int));
    // the pointer is never returned so the memory cannot be freed,
    // even by the caller
}

int main() {
    performUselessAllocation(10);
    // memory cannot be freed from here
}

We first define the following header clamp.h:

#pragma once // ensures the header is included only once

#include <stddef.h>
#include <stdint.h>

// Alias float types acording to <stdint.h>
typedef float float32_t;
typedef long float64_t;
typedef long double float128_t;

// Define the bodies for both signed and unsigned type
#define CLAMP_BODY_U(type) \
    type clamp_##type(type val, type min, type max) { \
        return (val < min) ? min : (val > max) ? max: val; \
    } \
    \
    unsigned type clamp_u##type(unsigned type val, unsigned type min, unsigned type max) { \
        return (val < min) ? min : (val > max) ? max: val; \
    }

// Define the body for only the signed type
#define CLAMP_BODY(type) \
    type clamp_##type(type val, type min, type max) { \
        return (val < min) ? min : (val > max) ? max: val; \
    }

/**
 * @brief A generic clamp function.
 * 
 * @param val The value to clamp.
 * @param min The minimum value.
 * @param max The maximum value.
 * @return The value after clamping.
 */
#define clamp(val, min, max) \
    _Generic((val), \
    char: clamp_char, \
    unsigned char: clamp_uchar, \
    int8_t: clamp_int8_t, \
    uint8_t: clamp_uint8_t, \
    int16_t: clamp_int16_t, \
    uint16_t: clamp_uint16_t, \
    int32_t: clamp_int32_t, \
    uint32_t: clamp_uint32_t, \
    int64_t: clamp_int64_t, \
    uint64_t: clamp_uint64_t, \
    float32_t: clamp_float32_t, \
    float64_t: clamp_float64_t \
    float128_t: clamp_float128_t \
    size_t: clamp_size_t \
    ptrdiff_t: clamp_ptrdiff_t
)(val, min, max)

CLAMP_BODY_U(char);
CLAMP_BODY_U(int8_t);
CLAMP_BODY_U(int16_t);
CLAMP_BODY_U(int32_t);
CLAMP_BODY_U(int64_t);
CLAMP_BODY(float32_t);
CLAMP_BODY(float64_t);
CLAMP_BODY(float128_t);
CLAMP_BODY(size_t);
CLAMP_BODY(ptrdiff_t);

Then in main.c:

#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>

#include "clamp.h"

/**
 * @brief Determines whether the tranny should ack based on a given probability.
 *
 * @param ackProbability An (unsigned) integer between 0 and 100 representing the chance of acking.
 * @return True if the random probability is less than the ackProbability; otherwise, False.
 */
bool shouldAck(unsigned int ackProbability) {
    return (rand() % 101) < (float)clamp(ackProbability, 0, 100);
}

/**
 * @brief Main function that decides whether to ack or scream TRANS RIGHTS ARE HUMAN RIGHTS!!!!!!!! based on probability.
 *
 * @param argc The number of command line arguments.
 * @param argv An array of command line arguments.
 * @return Whether the program executed successfully.
 */
int main(int argc, char *argv[]) {
    srand((unsigned int)time(nullptr));
    if (shouldAck(41)) {
        fprintf(stderr, "%s\n", "ACK!!!");
        raise(SIGSEGV);
    } else {
        printf("%s\n", "TRANS RIGHTS ARE HUMAN RIGHTS!!!");
    }
    return 0;
}

Before C23, you had to include <stdbool.h> because booleans were not a core primitive type in the language, also there was no nullptr so you had to use NULL.

#include <signal.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>

#define clamp(val, min, max) (val < min) ? min : (val > max) ? max: val; 

/**
 * @brief Determines whether the tranny should ack based on a given probability.
 *
 * @param ackProbability An (unsigned) integer between 0 and 100 representing the chance of acking.
 * @return True if the random probability is less than the ackProbability; otherwise, False.
 */
bool shouldAck(unsigned int ackProbability) {
    return (rand() % 101) < (float)clamp(ackProbability, 0, 100);
}

/**
 * @brief Main function that decides whether to ack or scream TRANS RIGHTS ARE HUMAN RIGHTS!!!!!!!! based on probability.
 *
 * @param argc The number of command line arguments.
 * @param argv An array of command line arguments.
 * @return Whether the program executed successfully.
 */
int main(int argc, char *argv[]) {
    srand((unsigned int)time(NULL));
    if (shouldAck(41)) {
        fprintf(stderr, "%s\n", "ACK!!!");
        // alternatively: fputs("ACK!!!\n", stderr);
        raise(SIGSEGV);
    } else {
        printf("%s\n", "TRANS RIGHTS ARE HUMAN RIGHTS!!!");
        // alternatively: puts("TRANS RIGHTS ARE HUMAN RIGHTS!!!");
    }
    return 0;
}

To compile make a nuproject under "Win32 Application" and choose Blank Application. in MSVC 4.2 portable, make a Main.c file in the project folder and paste it in then include it in the project, compile it and run it.

#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <windows.h>

#include "clamp.h"

/**
 * @brief Determines whether the tranny should ack based on a given probability.
 *
 * @param ackProbability An (unsigned) integer between 0 and 100 representing the chance of acking.
 * @return True if the random probability is less than the ackProbability; otherwise, False.
 */
bool shouldAck(unsigned int ackProbability) {
    clamp(ackProbability, 0, 100);
    return (rand() % 101) < (float)clamp(ackProbability, 0, 100);
}

/**
 * @brief Main function that decides whether to ack or scream TRANS RIGHTS ARE HUMAN RIGHTS!!!!!!!! based on probability.
 *
 * @param hInstance Handle to the current instance of the application.
 * @param hPrevInstance Handle to the previous instance of the application.
 * @param lpCmdLine Command line arguments passed to the application.
 * @param nCmdShow Specifies how the window is to be shown.
 * @return Whether the program executed successfully.
 */
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) {
    char message[256];
    srand((unsigned int)time(nullptr));
    
    if (shouldAck(41)) {
        // Show "ACK!!!" message box
        MessageBox(nullptr, "ACK!!!", "Result", MB_OK | MB_ICONINFORMATION);
	    const char msg[] = "ACK!!!";
	    WriteConsoleA(GetStdHandle(STD_OUTPUT_HANDLE), msg, strlen(msg), nullptr, nullptr);
    } else {
        // Show "TRANS RIGHTS ARE HUMAN RIGHTS!!!" message box
        MessageBox(nullptr, "TRANS RIGHTS ARE HUMAN RIGHTS!!!", "Result", MB_OK | MB_ICONINFORMATION);
	    const char msg[] = "TRANS RIGHTS ARE HUMAN RIGHTS!!!";
	    WriteConsoleA(GetStdHandle(STD_OUTPUT_HANDLE), msg, strlen(msg), nullptr, nullptr);
    }

    return 0;
}