排序算法C语言代码_c语言排序代码

1.快速排序

void quicksort(int* a,int left,int right){
    if(left>=right)return ;
    int begin=left,end=right;
    int pivot=begin,key=a[begin];
 
 
    while(begin<end){
        while(begin<end&&a[end]>=key){
            end--;
        }
        a[pivot]=a[end];
        pivot=end;
        while(begin<end&&a[begin]<=key){
            begin++;
        }
        a[pivot]=a[begin];
        pivot=begin;
    }
    a[pivot]=key;
    quicksort(a,left,pivot-1);
    quicksort(a,pivot+1,right);
}

2.冒泡排序

void bubble_sort(int* a,int len){
    int i,j,temp;
    for(i=0;i<len-1;i++){
        int cnt=0;
        for(int j=0;j<len-1-i;j++){
            if(a[j]>a[j+1]){
                temp=a[j];
                a[j]=a[j+1];
                a[j+1]=temp;
                cnt=1;
            }
        }
        //一趟下来没有交换任何位置，则证明已排好序
        if(cnt==0){
            break;
        }
    }
}

3.插入排序

void insert_sort(int* a,int len){
    int i,j,temp;
    for(int i=1;i<len;i++){
        temp=a[i];
        j=i-1;
        while(j>=0&&a[j]>temp){
            a[j+1]=a[j];
            j--;
        }
        a[j+1]=temp;
    }
}

4.希尔排序

void shell_sort(int* a,int len){
    int  i,j;
    int gap=0;
    int temp=0,k;
    for(int gap=len/2;gap>0;gap/=2){
        for(i=0;i<gap;i++){
            for(j=i+gap;j<len;i+=gap){
                temp=a[j];
                k=j-gap;
                while(k>=0&&a[k]>temp){
                    a[k+gap]=a[k];
                    k-=gap;
                }
                a[k+gap]=temp;
            }
        }
    }
}

5.选择排序

void select_sort(int* a,int len){
    int i,j,min,index;
    int temp=0;
    for(int i=0;i<len-1;i++){
        min=a[i];
        index=i;
        for(j=i+1;j<len;j++){
            if(a[j]<min)
            {
                min=a[j];
                index=j;
            }
        }
        if(index!=i)
        {
            temp=a[i];
            a[i]=a[index];
            a[index]=temp;
        }
    }
}

6.归并排序

void merge(int* a,int left,int mid,int right){
    int i=left,j=mid+1,index=0;
    int* newarr=(int* )malloc((right-left+1)*sizeof(int));
    if(newarr==NULL)
    {
        printf("malloc error");
        exit(1);
    }
    while(i<=mid&&j<=right){
        if(a[i]<a[j])newarr[index++]=a[i++];
        else newarr[index++]=a[j++];
    }
    while(i<=mid)
        newarr[index++]=a[i++];
    while(j<=right)
        newarr[index++]=a[j++];
    for(i=left,index=0;index<(right-left+1);i++,index++){
        a[i]=newarr[index++];
    }
    free(newarr);
}
void merge_sort(int* a,int low,int high){
    if(low>=high)return ;
    int mid=(high-low)/2;
    merge_sort(a,low,mid);
    merge_sort(a,mid+1,high);
    merge(a,low,mid,high);
}

7.基数排序

int get_max(int a[], int n) {
	int i, max;
	max = a[0];
	for (i = 1; i < n; i++) {
		if (a[i] > max) {
			max = a[i];
		}
	}
	return max;
}
 
 
void count_sort(int a[], int n, int exp) {
	int *output = (int *)malloc(n*sizeof(int));
	int i, buckets[10] = { 0 };
	for (i = 0; i < n; i++) {
		buckets[(a[i] / exp) % 10]++;
	}
	for (i = 1; i < 10; i++) {
		buckets[i] += buckets[i - 1];
	}
	for (i = n - 1; i >= 0; i--) {
		output[buckets[(a[i] / exp) % 10] - 1] = a[i];
		buckets[(a[i] / exp) % 10]--;
	}
	
	for (i = 0; i < n; i++) {
		a[i] = output[i];
	}
}
 
void radix_sort(int a[], int n) {
	int exp;
	int max = get_max(a, n);
	for (exp = 1; max / exp > 0; exp *= 10) {
		count_sort(a, n, exp);
	}
}
 

8 堆排序

void swap(int* a, int* b) {
	int tmp = *a;
	*a = *b;
	*b = tmp;
}
 
 
void maxheap_sort(int *a, int start,int end) {
	int c = start; 
	int l = 2 * c + 1; 
	int tmp = a[c];
	for (; l <= end; c = l, l = 2 * l + 1) {
		if (l < end && a[l] < a[l + 1]) {
			l++; 
		}
		if (tmp >= a[l]) {
			break; 
		}
		else {
			a[c] = a[l];
			a[l] = tmp;
		}
	}
}
 
 
void heap_sort_asc(int a[], int n) {
	int i;
	for (i = n / 2 - 1; i >= 0; i--) {
		maxheap_sort(a, i, n - 1);
	}
	for (i = n - 1; i > 0; i--) {
		swap(&a[0], &a[i]);
		maxheap_sort(a, 0, i - 1);
	}
}