c
复制代码
// 按x降序，按y升序
int cmp(const void *a, const void *b) {
int *p = *(int **)a;
int *q = *(int **)b;
if(p[0] == q[0]){
return p[1]-q[1];
}
else return q[0]-p[0];
}
// 判断c点是否在a为右下角，b为左上角的矩形和边界内
bool IsPad(int *pointa, int *pointb, int *pointc) {
return !(pointc[0] > pointa[0] || pointc[0] < pointb[0] || pointc[1] < pointa[1] || pointc[1] > pointb[1]);
}
int numberOfPairs(int** points, int pointsSize, int* pointsColSize) {
int res = 0;
qsort(points, pointsSize, sizeof(int *), cmp);
for(int i=0; i<pointsSize; i++) {
for(int j=i+1; j<pointsSize; j++) {
if(points[j][1] < points[i][1]){
continue;
}
int k=i+1;
while(k<j) {
if(IsPad(points[i], points[j], points[k])) break;
k++;
}
if(k == j) res++;
}
}
return res;
}