#include <stdio.h>
#include <string.h>

typedef struct {
    int x;
    float y;
    char s[256];
} my_struct_t;

void f1(my_struct_t m) {
    m.x = 10;
}

void f2(my_struct_t* m) {
    m->x = 10;
}

int main() {
    my_struct_t t1;
    t1.x = 1;
    t1.y = 2;
    strncpy(t1.s, "3", 256);
    my_struct_t t2;
    t2.x = 4;
    t2.y = 5;
    strncpy(t2.s, "6", 256);

    t1 = t2;

    return 0;
}