第三题怎么使用函数调用来解决

#include <stdio.h>
#include<math.h>
double distance(int x1,int y1,int x2,int y2){
    return sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
}
int main(void) {
    int x1,y1,x2,y2; 
    printf("输入第一个点的坐标：");
    scanf("%d %d",&x1,&y1);
    printf("输入第二个点的坐标：");
    scanf("%d %d",&x2,&y2);
    printf("距离：%lf",distance(x1,y1,x2,y2));
    return 0;
}

#include <stdio.h>
#include <math.h>

double distance(int x1,int y1,int x2,int y2);

int main(void){
    int x1,y1,x2,y2; 
    
    scanf("%d %d %d %d",&x1,&y1,&x2,&y2);
    
    printf("distance:%lf",distance(x1,y1,x2,y2));
}

double distance(int x1,int y1,int x2,int y2){
     
    return sqrt((x1-x2)*(x1-x2) + (y1-y2)*(y1-y2) );
    
}

这样应该可以实现你需要的效果

#include < math.h >
double distance = sqrt(pow(double(x1 - x2), 2) - pow(double(y1 - y2), 2));