#include<stdio.h>                    
void main()                    
{                    
    int c[19],i[7],j;
   
    int a[2]={c[i[2]]-c[i[1]]-c[i[0]],i[2]-i[1]-i[0]};
                    
                    
                    
printf("请输入(1)个整数: \n");                    
for(j=0;j<19;j++)                    
    scanf("%d",&c[j]);               
printf("\n");                    
                    
for(j=0;j<7;j++)                    
    scanf("%d",&i[j]);               
printf("\n");                    
                    
                    
                    
    printf("%d  ",a[0]);               
    printf("%d  ",a[1]);
   if(a[1]!=0)
    printf("%f \n",a[0]/a[1]);
    printf("\n");

}


实验输入数据：

7 8 9 14 16 18 20 21 25 33 34 41 46 47 52 56 60 61 62                    
                                       
2   5   11   12   13   14   16                    

[此贴子已经被作者于2017-1-26 18:29编辑过]

int a[2]={c[i[2]]-c[i[1]]-c[i[0]],i[2]-i[1]-i[0]};
没有赋初值~还有c[i[2]]可能会越界~

#include<stdio.h>                    
void main()                    
{                    
    int c[19],i[7],j;
   
   
                    
                    
                    
printf("请输入(1)个整数: \n");                    
for(j=0;j<19;j++)                    
    scanf("%d",&c[j]);               
printf("\n");                    
                    
for(j=0;j<7;j++)                    
    scanf("%d",&i[j]);               
printf("\n");     
 int a[2]={c[i[2]]-c[i[1]]-c[i[0]],i[2]-i[1]-i[0]};    //              
                    
                    
                    
    printf("%d  ",a[0]);               
    printf("%d  ",a[1]);
   if(a[1]!=0)
    printf("%f \n",1.0*a[0]/a[1]);              //1.0*
    printf("\n");

}

感谢指教!难题有解了！
#include<stdio.h>   
            
void main()                    
{                    
    int c[19]={7 ,8, 9 ,14 ,16 ,18 ,20 ,21, 25, 33, 34, 41, 46 ,47 ,52, 56, 60 ,61 ,62   },
        
        i[7]={2  , 5 ,  11  , 12 ,  13  , 14 ,  16},j,   
   
     a[2]={c[i[2]]-c[i[1]]-c[i[0]],i[2]-i[1]-i[0]};
                           
    printf("%d  ",a[0]);               
    printf("%d  ",a[1]);
    if(a[1]!=0)
    printf("%f \n",1.0*a[0]/a[1]);
    printf("\n");

}

14  4  3.500000

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排序难题解决了；
#include<stdio.h>   
#include<stdlib.h>               
               
int commp(const void *a, const void *b)               
{               
return *(int *)a > *(int *)b ? 1 : -1;               
}               
main()                    
{                    
    int c[19]={7 ,8, 9 ,14 ,16 ,18 ,20 ,21, 25, 33, 34, 41, 46 ,47 ,52, 56, 60 ,61 ,62   },
        
        i[7]={2  , 5 ,  11  , 12 ,  13  , 14 ,  16},j,   
   
        a[2][2]={{c[i[2]]-c[i[1]]-c[i[0]],i[2]-i[1]-i[0]},{c[i[3]]-c[i[2]]-c[i[1]],i[3]-i[2]-i[1]}};
     
    qsort(a, sizeof(a)/sizeof(int)/2, 2*sizeof(int ),commp);                        
                        
 for(j = 0; j < sizeof(a)/sizeof(int )/2; j++)                        
 {                        
if(a[j][1] != 0)                        
{                        
printf("%d\n", a[j][0]);    printf("%d\n%d\n%d\n%d\n", a[0][0], a[0][1], a[1][0], a[1][1]);

printf("%f\n", 1.0*a[0][1]/a[0][0]);   
                        
printf("\n");                        
break;                        
}                        
 }                        
                        
 return 0;                        
               
}                                       
            
-13
-13
-4
14
4
0.307692

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