c programming is error。why？

#include <stdio.h>
#include <string.h>
int main()
{
	float weigh, volume;
	int size, letters;
	char name[40];
	printf("What's your name ?\n");
	scanf("%s", name);
	printf("%s,and your weight ?\n", name);
	scanf("%f", &weigh);

	return 0;

}