原理：

代碼：

- (void)selectionSort {
    int a[] = {7,1,3,5,8,10,9,2,4,6,19,22,0,33};
    int length = sizeof(a)/sizeof(a[0]);
    
    printfLog(a,length);
    
    int minIndex;
    
    for (int i = 0; i < length - 1; i++) {
        minIndex = i;
        for (int j = i + 1; j < length; j++) {
            if (a[j] < a[minIndex]) {     //尋找最小的數(shù)
                minIndex = j;                 //將最小數(shù)的索引保存
            }
        }
        swap(&a[i], &a[minIndex]);
    }
    
    printfLog(a,length);
}

void swap(int *a, int *b) {
    int temp = *a;
    *a = *b;
    *b = temp;
}

void printfLog(int a[],int length) {
    for (int i = 0; i < length; i++) {
        printf("%d ",a[i]);
    }
    printf("\n");
}