【求助，C语言】我测试了一组整数解，求的是对的，为什么过不了测评

在vs2022编译器上进行了测试，过了 但是过不了洛谷的测评，求助

#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<math.h>
typedef double ele;
struct point {
    ele x; ele y;
};
int dis(struct point a, struct point b) {
    return sqrt(      (a.x - b.x)* (a.x - b.x) + (a.y - b.y)*(a.y - b.y)       );
}
int main() {
    struct point inp[3];
    int r;
    for (r = 0; r < 3; r++) {
        scanf("%lf %lf", &inp[r].x, &inp[r].y);
    }
    ele ans = 0;
    for (r = 0; r < 2; r++) {
        ans += dis(inp[r], inp[r + 1]);
    }
    ans += dis(inp[2], inp[0]);
    printf("%.2lf", ans);
}