c_cpp 计数排序

Posted 2021-05-14

#include<stdio.h>
void countingsort(int* a, int n, int max){
    int b[n],c[max+1],i;
    for(i=0; i<=max; i++)
        c[i] = 0;
    for(i=0; i<n; i++)
        c[a[i]]++;
    for(i=1; i<=max; i++)
        c[i] = c[i]+c[i-1];
    for(i=n-1; i>=0; i--){
        b[c[a[i]]-1] = a[i];
        c[a[i]]--;
    }
    for(i=0; i<n; i++)
        a[i] = b[i];
}

int main(){
    int n;
    printf("Enter size of array\n");
    scanf("%d",&n);
    int a[n],i,max;
    printf("Enter elements of array\n");
    scanf("%d",&a[0]);
    max = a[0];
    for(i=1; i<n; i++){
        scanf("%d",&a[i]);
        if(a[i] > max) max=a[i];
    }
    countingsort(a,n,max);
    printf("Sorted array:\n");
    for(i=0; i<n; i++)
        printf("%d ",a[i]);
    return 0;
}