diff --git a/c-1/Makefile b/c-1/Makefile
new file mode 100644
index 0000000..61a79b1
--- /dev/null
+++ b/c-1/Makefile
@@ -0,0 +1,37 @@
+CC=gcc
+CFLAGS=-O3 -march=native -flto -Wall
+
+# Get all .c files in the current directory
+SOURCES=$(wildcard *.c)
+# Create a list of executable names from the .c files
+TARGETS=$(SOURCES:.c=)
+
+# Default target: build all executables
+all: $(TARGETS)
+
+# General rule for programs with no special libs
+%: %.c
+	$(CC) $(CFLAGS) -o $@ $<
+
+# Specific rules for programs with special libs
+password_hash: password_hash.c
+	$(CC) $(CFLAGS) -o $@ $< -largon2
+
+sha256: sha256.c
+	$(CC) $(CFLAGS) -o $@ $< -lcrypto
+
+gmp_init: gmp_init.c
+	$(CC) $(CFLAGS) -o $@ $< -lgmp
+
+gmp_mul: gmp_mul.c
+	$(CC) $(CFLAGS) -o $@ $< -lgmp
+
+gmp_add: gmp_add.c
+	$(CC) $(CFLAGS) -o $@ $< -lgmp
+
+gmp_div: gmp_div.c
+	$(CC) $(CFLAGS) -o $@ $< -lgmp
+
+# Target to clean up all compiled binaries
+clean:
+	rm -f $(TARGETS)
diff --git a/c/date_math_add.c b/c-1/date_math_add.c
similarity index 100%
rename from c/date_math_add.c
rename to c-1/date_math_add.c
diff --git a/c/date_math_subtract.c b/c-1/date_math_subtract.c
similarity index 100%
rename from c/date_math_subtract.c
rename to c-1/date_math_subtract.c
diff --git a/c/get_time.c b/c-1/get_time.c
similarity index 100%
rename from c/get_time.c
rename to c-1/get_time.c
diff --git a/c/gmp_add.c b/c-1/gmp_add.c
similarity index 100%
rename from c/gmp_add.c
rename to c-1/gmp_add.c
diff --git a/c/gmp_div.c b/c-1/gmp_div.c
similarity index 100%
rename from c/gmp_div.c
rename to c-1/gmp_div.c
diff --git a/c/gmp_init.c b/c-1/gmp_init.c
similarity index 100%
rename from c/gmp_init.c
rename to c-1/gmp_init.c
diff --git a/c/gmp_mul.c b/c-1/gmp_mul.c
similarity index 100%
rename from c/gmp_mul.c
rename to c-1/gmp_mul.c
diff --git a/c/hexdec.c b/c-1/hexdec.c
similarity index 100%
rename from c/hexdec.c
rename to c-1/hexdec.c
diff --git a/c/microtime.c b/c-1/microtime.c
similarity index 100%
rename from c/microtime.c
rename to c-1/microtime.c
diff --git a/c/password_hash.c b/c-1/password_hash.c
similarity index 100%
rename from c/password_hash.c
rename to c-1/password_hash.c
diff --git a/c/sha256.c b/c-1/sha256.c
similarity index 100%
rename from c/sha256.c
rename to c-1/sha256.c
diff --git a/c/substr.c b/c-1/substr.c
similarity index 100%
rename from c/substr.c
rename to c-1/substr.c
diff --git a/c-gpu-1/Makefile b/c-gpu-1/Makefile
new file mode 100644
index 0000000..04bf0f3
--- /dev/null
+++ b/c-gpu-1/Makefile
@@ -0,0 +1,27 @@
+# --- CUDA Configuration ---
+# Check if nvcc is available
+NVCC := $(shell command -v nvcc 2> /dev/null)
+NVCCFLAGS=-O3 --std=c++11
+
+# --- argon2-gpu Library ---
+ARGON2_GPU_DIR=../argon2-gpu
+ARGON2_GPU_INCLUDE_DIR=$(ARGON2_GPU_DIR)/include
+ARGON2_GPU_LIB_DIR=$(ARGON2_GPU_DIR)
+ARGON2_GPU_LIBS=-L$(ARGON2_GPU_LIB_DIR) -largon2-cuda -largon2-gpu-common
+
+TARGETS =
+ifdef NVCC
+    TARGETS += password_hash_gpu
+endif
+
+# Default target: build all executables
+all: $(TARGETS)
+
+ifdef NVCC
+password_hash_gpu: password_hash_gpu.cu
+	$(NVCC) $(NVCCFLAGS) -I$(ARGON2_GPU_INCLUDE_DIR) -o $@ $< $(ARGON2_GPU_LIBS) -largon2
+endif
+
+# Target to clean up all compiled binaries
+clean:
+	rm -f $(TARGETS)
diff --git a/c/password_hash_gpu.cu b/c-gpu-1/password_hash_gpu.cu
similarity index 100%
rename from c/password_hash_gpu.cu
rename to c-gpu-1/password_hash_gpu.cu
diff --git a/c-php-sourced/gmp_add.c b/c-php-sourced/gmp_add.c
new file mode 100644
index 0000000..2d2b121
--- /dev/null
+++ b/c-php-sourced/gmp_add.c
@@ -0,0 +1,41 @@
+// C implementation to mirror the functionality of php/gmp_add.php
+// Based on the existing C implementation in c-1/gmp_add.c for consistency.
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <gmp.h>
+
+int main(int argc, char *argv[]) {
+    if (argc != 4) {
+        fprintf(stderr, "Usage: %s <num_a> <num_b> <iterations>\\n", argv[0]);
+        return 1;
+    }
+
+    char *a_str = argv[1];
+    char *b_str = argv[2];
+    int iterations = atoi(argv[3]);
+
+    mpz_t a, b, result;
+    mpz_init_set_str(a, a_str, 10);
+    mpz_init_set_str(b, b_str, 10);
+    mpz_init(result);
+
+    struct timespec start, end;
+    clock_gettime(CLOCK_MONOTONIC, &start);
+
+    for (int i = 0; i < iterations; i++) {
+        mpz_add(result, a, b);
+    }
+
+    clock_gettime(CLOCK_MONOTONIC, &end);
+
+    double time_spent = (end.tv_sec - start.tv_sec) + (end.tv_nsec - start.tv_nsec) / 1000000000.0;
+    printf("%.12f\\n", time_spent);
+
+    mpz_clear(a);
+    mpz_clear(b);
+    mpz_clear(result);
+
+    return 0;
+}
diff --git a/c-php-sourced/gmp_div.c b/c-php-sourced/gmp_div.c
new file mode 100644
index 0000000..67f44f0
--- /dev/null
+++ b/c-php-sourced/gmp_div.c
@@ -0,0 +1,41 @@
+// C implementation to mirror the functionality of php/gmp_div.php
+// Based on the existing C implementation in c-1/gmp_div.c for consistency.
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <gmp.h>
+
+int main(int argc, char *argv[]) {
+    if (argc != 4) {
+        fprintf(stderr, "Usage: %s <num_a> <num_b> <iterations>\\n", argv[0]);
+        return 1;
+    }
+
+    char *a_str = argv[1];
+    char *b_str = argv[2];
+    int iterations = atoi(argv[3]);
+
+    mpz_t a, b, result;
+    mpz_init_set_str(a, a_str, 10);
+    mpz_init_set_str(b, b_str, 10);
+    mpz_init(result);
+
+    struct timespec start, end;
+    clock_gettime(CLOCK_MONOTONIC, &start);
+
+    for (int i = 0; i < iterations; i++) {
+        mpz_div(result, a, b);
+    }
+
+    clock_gettime(CLOCK_MONOTONIC, &end);
+
+    double time_spent = (end.tv_sec - start.tv_sec) + (end.tv_nsec - start.tv_nsec) / 1000000000.0;
+    printf("%.12f\\n", time_spent);
+
+    mpz_clear(a);
+    mpz_clear(b);
+    mpz_clear(result);
+
+    return 0;
+}
diff --git a/c-php-sourced/password_hash.c b/c-php-sourced/password_hash.c
new file mode 100644
index 0000000..401bf20
--- /dev/null
+++ b/c-php-sourced/password_hash.c
@@ -0,0 +1,43 @@
+// Source: https://github.com/php/php-src/blob/master/ext/standard/password.c
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include "argon2.h"
+
+#define HASHLEN 32
+#define SALTLEN 16
+
+int main(int argc, char **argv) {
+    if (argc != 3) {
+        fprintf(stderr, "Usage: %s <password> <iterations>\\n", argv[0]);
+        return 1;
+    }
+
+    char *pwd = argv[1];
+    int iterations = atoi(argv[2]);
+
+    uint8_t salt[SALTLEN];
+    memset(salt, 0x00, SALTLEN); // For simplicity, using a fixed salt for the benchmark.
+
+    uint32_t t_cost = 2; // time_cost
+    uint32_t m_cost = 32768; // memory_cost in KiB
+    uint32_t parallelism = 1; // threads
+
+    char hash[HASHLEN];
+
+    struct timespec start, end;
+    clock_gettime(CLOCK_MONOTONIC, &start);
+
+    for (int i = 0; i < iterations; i++) {
+        argon2i_hash_raw(t_cost, m_cost, parallelism, pwd, strlen(pwd), salt, SALTLEN, hash, HASHLEN);
+    }
+
+    clock_gettime(CLOCK_MONOTONIC, &end);
+
+    double time_spent = (end.tv_sec - start.tv_sec) + (end.tv_nsec - start.tv_nsec) / 1000000000.0;
+    printf("%.12f\\n", time_spent);
+
+    return 0;
+}
diff --git a/c-php-sourced/sha256.c b/c-php-sourced/sha256.c
new file mode 100644
index 0000000..e61e8b8
--- /dev/null
+++ b/c-php-sourced/sha256.c
@@ -0,0 +1,33 @@
+// Implementation based on OpenSSL's libcrypto, mirroring the original c/sha256.c test.
+// Source for PHP's hash function is complex to isolate, so this provides a standard C equivalent.
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <openssl/sha.h>
+
+int main(int argc, char **argv) {
+    if (argc != 3) {
+        fprintf(stderr, "Usage: %s <string> <iterations>\\n", argv[0]);
+        return 1;
+    }
+
+    char *string = argv[1];
+    int iterations = atoi(argv[2]);
+    unsigned char hash[SHA256_DIGEST_LENGTH];
+
+    struct timespec start, end;
+    clock_gettime(CLOCK_MONOTONIC, &start);
+
+    for (int i = 0; i < iterations; i++) {
+        SHA256((unsigned char*)string, strlen(string), hash);
+    }
+
+    clock_gettime(CLOCK_MONOTONIC, &end);
+
+    double time_spent = (end.tv_sec - start.tv_sec) + (end.tv_nsec - start.tv_nsec) / 1000000000.0;
+    printf("%.12f\\n", time_spent);
+
+    return 0;
+}