#include<stdio.h>void main(){ double y,l; printf("plaese enter the values of yingcun \n"); scanf("%lf",&y); l=y*2.54; printf("it is %lf cm\n",l);}或者#include<stdio.h>int main(){ double y,l; printf("plaese enter the values of yingcun \n"); scanf("%lf",&y); l=y*2.54; printf("it is %lf cm\n",l); return 0;}