Display two array elements in C

Question

I need to show the matching "dates" element with the "values" element. I'm having trouble trying to show the two arrays' elements together. For example, I need to get the highest rainfall value to show the year and month it occurred. Same with lowest etc. I have used a for loop to find the highest and lowest values of rainfall that occurred but I am unsure on how to print the corresponding date.

I think I am on the right track but have gotten to this point and don't know what to do!

I would appreciate some help with this and maybe some tips to keep in my mind if you have any to share. P.S I'm new to stackoverflow.

Example when executed

My code so far:

#include <stdio.h>
#include <stdlib.h>
    
int main()
{
    // Data Declaration
    char header[40] = "";
    int size_of_array = 768;
    int dates[768] = {0};
    float values[768] = {0};
    float sum = 0;
    float sum1 = 0;
    float avg;
    int i;
    float largest, lowest;
    FILE *input_fptr;
    
    //  Opens file
    input_fptr = fopen("rainfallupdated.csv", "r");
    if( input_fptr == NULL )
    {
        printf( "Error - could not open the file\n");
        return 1;
    }
    
    // Read in the header line from file
    fgets(header, sizeof(header), input_fptr);
    printf("%s", header);
    
    // Read 768 lines of data from the file
    for( i=0; i < size_of_array; i++)
    {
        fscanf(input_fptr, "%d,%f\n", &dates[i], &values[i]);
        printf( "%d\t %g\n", dates[i], values[i]);
    
    }
    fclose(input_fptr);
    
    // Information for the user
    printf("YearMonth , Rainfall in mm\n");
    printf("\n");
    printf("Example: 198702 -> February of 1987.\n");
    printf("\n");
    printf("--------------------------------------------------\n");
    printf("--------------------------------------------------\n");
    printf("\n");
    
    
    // Total rainfall
    for (i=0; i < size_of_array; i++)
    {
        sum = sum + values[i];
    }
    
    printf("Sum of all rainfall values -> %.2f mm\n", sum);
    printf("\n");
    
    // Average rainfall
    avg = sum / size_of_array;
    
    printf("Average rainfall value -> %.2f mm\n", avg);
    printf("\n");
    printf("--------------------------------------------------\n");
    printf("--------------------------------------------------\n");
    printf("\n");
    
    // Largest and Lowest rainfall values
    largest=values[0];
    for(i=0; i < size_of_array; i++)
    {
        if(values[i]>largest)
        largest=values[i];
    }
    lowest=values[0];
    
    for(i=0; i < size_of_array; i++)
    {
        if(values[i]<lowest)
        lowest=values[i];
    }
    
    printf("The highest rainfall value -> %.2f mm\n", largest);
    printf("\n");
    printf("The lowest rainfall value -> %.2f mm\n", lowest);
    printf("\n");
    
    /* for (i=0; i < 12; i++)
    {
        sum1 = sum1 + values[i];
    }
    
    printf("Total rainfall for 1958 -> %.2f mm\n", sum1); */
    
    return 0;
}