【十二题解】 | #图片整理#(归并排序)

归并真的是又简单又快

#include<stdio.h>

void merge(chara, chartmp, int l, int r, int rightend){

int lenth = rightend-l+1;
int leftend = r-1;
int loc = l;
while(l<=leftend && r<=rightend){
    if(a[l]>a[r]){
        tmp[loc++]=a[r++];
    }
    else{
        tmp[loc++]=a[l++];
    }
}
while(l<=leftend)tmp[loc++]=a[l++];
while(r<=rightend)tmp[loc++]=a[r++];
while(lenth!=0){
    a[rightend--]=tmp[rightend];
    lenth--;
}

}

void mort(chara, chartmp, int l , int rightend){

int center;
if(l<rightend){
    center = (rightend+l)/2;
    mort(a, tmp, l, center);
    mort(a, tmp, center+1, rightend);
    merge(a, tmp, l, center+1, rightend);
}

}

void mort_sort(char*a, int number){

char*tmp = (char*)malloc(sizeof(char)*number);
mort(a, tmp, 0, number-1);

}

int main(){

char data[1000]={0};
while(scanf("%s", data) != -1){
    int lenth;
    for(lenth = 0; data[lenth]!='\0'; lenth++);
    mort_sort(data, lenth);
    for (int i=0; i<lenth; i++){
    printf("%c", data[i]);
    }
    printf("\n");
}

}