Recursive min problem

[Petr_Kropotkin]

I am given a matrix and size.

const int MAX=50;
int min;
int mat[];
int FindMin(int mat[MAX],int size)
{
if (size==0)
return 0;
 
 
 min=mat[0];
 
if (mat[size]<min)
   min=mat[size];
else return FindMin(mat,size-1);
 }
 
main()
{
int i;
srand(time(0));
for(i=0;i<MAX;++i)
mat[i]=1+rand()%MAX;
cout<<"min-="<<<min

const int MAX=50;
int min;
int mat[];
int FindMin(int mat[MAX],int size)
{
if (size==0)
return 0;

 
 min=mat[0];

if (mat[size]<min)
   min=mat[size];
else return FindMin(mat,size-1);
 }

main()
{
int i;
srand(time(0));
for(i=0;i<MAX;++i)
mat[i]=1+rand()%MAX;
cout<<"min-="<<<min

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This code far from works all the time. How can I make it work ?

[caduel]

i) note that for an array of size n, the last valid index is n-1
ii) standard recursion (not efficient, btw)

int FindMin(int mat[MAX],int size)
{
    if (size==0) return 0;
 
    int min = FindMin(mat, size-1);
    return std::min(min, mat[size-1]);
}

int FindMin(int mat[MAX],int size)
{
    if (size==0) return 0;

    int min = FindMin(mat, size-1);
    return std::min(min, mat[size-1]);
}

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iii) linear code (faster)

i

nt FindMin(int mat[MAX],int size)
{
    if (size==0) return 0;
    int min=mat[0];
    for (int=1; i<size; ++i)
        min=std::min(min,mat[i]);
    return min;
}

nt FindMin(int mat[MAX],int size)
{
    if (size==0) return 0;
    int min=mat[0];
    for (int=1; i<size; ++i)
        min=std::min(min,mat[i]);
    return min;
}

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iv) easiest way: do NOT INVENT THE WHEEL all over again

#include <algorithm>
int FindMin(int mat[MAX], int size)
{
    return *std::min_element(mat, mat+size)
 }

#include <algorithm>
int FindMin(int mat[MAX], int size)
{
    return *std::min_element(mat, mat+size)
 }

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for such trivial things, the stdlib already offers algorithm that work (if you use Qt classes, Qt offers such algorithms as well)


HTH