常见的排序

常见的排序

直接插入排序、二分插入排序、希尔排序、冒泡排序、快排、简单选择排序、归并排序

#include <iostream>
using namespace std;

/**
*插入排序
*/
//直接插入排序
void insertSort(char sourse[], int n) {
    for(int i=2; i<=n; ++i) {
        if(sourse[i]<sourse[i-1]) {
            sourse[0] = sourse[i];
            int j;
            for(j=i-1; sourse[j]>sourse[0]; --j) {
                sourse[j+1] = sourse[j];
            }
            sourse[j+1] = sourse[0];
        }
    }
}

//二分查找
int binarySearch(char sourse[], int low, int high, char aim) {
    int mid = (low + high)/2;
    while(low <= high) {
        if(sourse[mid] == aim) {
            low = mid;
            break;
        }
        if(sourse[mid] > aim) {
            high = mid - 1;
        } else {
            low = mid + 1;
        }
        mid = (low + high)/2;
    }

    return low;
}

//折半插入排序
void insertHalfSort(char sourse[], int n) {
    for(int i=2; i<=n; ++i) {
        if(sourse[i-1] > sourse[i]) {
            sourse[0] = sourse[i];
            int pos = binarySearch(sourse, 1, i-1, sourse[0]);
            for(int j=i-1; j>=pos; --j) {
                sourse[j+1] = sourse[j];
            }
            sourse[pos] = sourse[0];
        }
    }
}

//希尔排序
void shellSort(char sourse[], int n) {
    for(int step=n/2; step>=1; step=step/2) {
        for(int i=step+1; i<=n; ++i) {
            if(sourse[i] < sourse[i-step]) {
                sourse[0] = sourse[i];
                int j;
                for(j = i-step; sourse[0] < sourse[j] && j>0; j=j-step) {
                    sourse[j+step] = sourse[j];
                }
                sourse[j+step] = sourse[0];
            }
        }
    }
}



/************************************************************************************************************/



/**
*交换排序
*/
//冒泡排序
void bubbleSort(char sourse[], int n) {
    for(int i=1; i<n; ++i) {
        bool isChanged = false;
        for(int j=1; j<n-i+1; ++j) {
            if(sourse[j]>sourse[j+1]) {
                swap(sourse[j], sourse[j+1]);
                isChanged = true;
            }
        }
        if(!isChanged) {
            break;
        }
    }
}

//快排
int partition(char sourse[], int low, int high) {
    sourse[0] = sourse[low];
    while(low<high) {
        while(low<high && sourse[high] >= sourse[0])
            --high;
        sourse[low] = sourse[high];
        while(low<high && sourse[low] <= sourse[0])
            ++low;
        sourse[high] = sourse[low];
    }
    sourse[low]=sourse[0];
    return low;
}
void quickSort(char sourse[], int low, int high) {
    if(low >=high) {
        return;
    }
    int pos = partition(sourse,low,high);
    quickSort(sourse, low, pos-1);
    quickSort(sourse, pos+1, high);
}


/************************************************************************************************************/

/**
*选择排序
*/
//简单选择排序
void selectSort(char sourse[], int n) {
    for(int i=1; i<=n; ++i) {
        int minp  = i;
        for(int j=i; j<=n; ++j) {
            if(sourse[j]<sourse[minp]) {
                minp = j;
            }
        }
        swap(sourse[i], sourse[minp]);
    }
}


/**
*二路归并排序
*/
char medim[14];
void merge(char sourse[], int low, int mid, int high) {

    for(int i=low; i<=high; i++) {
        medim[i] = sourse[i];
    }
    int i=low, j=mid+1;
    int k=low;
    while(i<=mid && j<=high) {
        if(medim[i]<=medim[j]) {
            sourse[k]=medim[i];
            i++;
        } else {
            sourse[k]=medim[j];
            j++;
        }
        k++;
    }
    while(i<=mid) {
        sourse[k]=medim[i];
        i++;
        k++;
    }
    while(j<=high) {
        sourse[k]=medim[j];
        k++;
        j++;
    }

}
void mergeSort(char sourse[], int low, int high) {
    if(low >= high) {
        return;
    }
    int mid = (low + high)/2;
    mergeSort(sourse, low, mid);
    mergeSort(sourse, mid+1, high);
    merge(sourse, low, mid, high);
}



void show(char sourse[], int n) {
    for(int i=1; i<=n; i++) {
        cout<<sourse[i];
    }
    cout<<endl;
}

int main() {
    char sourse[]= {' ','j', 'k','d','g','e', 'l', 'm','h','a','n','f','c', 'i','b'};

//    insertSort(sourse, 14);
//    insertSort(sourse, 14);
//    shellSort(sourse, 14);
//    bubbleSort(sourse, 14);
//    quickSort(sourse, 1, 14);
//    selectSort(sourse, 14);
    mergeSort(sourse, 1, 14);
    show(sourse, 14);

    return 0;
}