sysy-data/performance/sy/median0.sy

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2024-01-09 19:48:14 +08:00
int n;
int meanless_calculation(int x, int y){
int i = 0;
int ret = 0;
while (i < x && i < y){
i = i + 1;
ret = ret + x + i;
}
return ret;
}
int swap(int arr[], int l, int r){
int curr = arr[l];
arr[l] = arr[r];
arr[r] = curr;
return meanless_calculation(l, r);
}
int median(int arr[], int begin, int end, int pos){
int pivot = arr[begin];
int l = begin;
int r = end + 1;
int xx = 0;
while (1 == 1){
while (l < r){
r = r - 1;
if(arr[r] < pivot){
break;
}
xx = xx + 1;
}
while (l < r){
l = l + 1;
if(arr[l] >= pivot){
break;
}
xx = xx - 1;
}
if (l == r) break;
else {
swap(arr, l, r);
}
}
arr[begin] = pivot;
swap(arr, begin, l);
if (l > pos) return median(arr, begin, l, pos);
if (l < pos) return median(arr, l + 1, end, pos);
return xx;
}
int a[10000000];
int main(){
n = getarray(a);
starttime();
median(a, 0, n-1, n/2);
stoptime();
putarray(n, a);
return a[n/2] % 256;
}