蛮力法求解凸包问题c语言

以下是使用蛮力法求解凸包问题的C语言代码：

#include <stdio.h>
#include <stdlib.h>

struct Point {
    int x, y;
};

int orientation(struct Point p, struct Point q, struct Point r) {
    int val = (q.y - p.y) * (r.x - q.x) - (q.x - p.x) * (r.y - q.y);
    if (val == 0) {
        return 0;
    } else if (val > 0) {
        return 1;
    } else {
        return 2;
    }
}

void convexHull(struct Point points[], int n) {
    if (n < 3) {
        return;
    }

    int hull[n];
    int hullSize = 0;

    int leftmost = 0;
    for (int i = 1; i < n; i++) {
        if (points[i].x < points[leftmost].x) {
            leftmost = i;
        }
    }

    int p = leftmost, q;
    do {
        hull[hullSize++] = p;
        q = (p + 1) % n;
        for (int i = 0; i < n; i++) {
            if (orientation(points[p], points[i], points[q]) == 2) {
                q = i;
            }
        }
        p = q;
    } while (p != leftmost);

    for (int i = 0; i < hullSize; i++) {
        printf("(%d, %d)\n", points[hull[i]].x, points[hull[i]].y);
    }
}

int main() {
    struct Point points[] = {{0, 3}, {1, 1}, {2, 2}, {4, 4},
                             {0, 0}, {1, 2}, {3, 1}, {3, 3}};
    int n = sizeof(points) / sizeof(points[0]);
    convexHull(points, n);
    return 0;
}

这段代码实现了蛮力法求解凸包问题，其中`struct Point`结构体用于表示二维平面上的点，`orientation`函数用于判断三个点的相对位置关系，`convexHull`函数用于求解凸包，`main`函数用于测试。