Why this C cod gives me error?

Question

#include<stdio.h>
int main(){

int a1=42;
char b1=66;
char b2='C';
float c1=4.2;
double d1=0.21;
printf("%d %c %10d %.1f %.2f %s",a1,b1,b2,c1,d1,"Bilim\n");

printf("%d byte\n",sizeof(char));
printf("%d byte\n",sizeof(int));
printf("%d byte\n",sizeof(short int));
printf("%d byte\n",sizeof(long int));
printf("%d byte\n",sizeof(float));
printf("%d byte\n",sizeof(double));

return 0;

}

Answer 1

they're just warnings. But i would still change each printf line. instead of using %d specifier, use: %ld instead. Then it won't throw warnings

Answer 2

They're format specifier warnings.

double -> %lf
sizeof -> unsigned int -> %u