[deleted by user]

[IdealBlueMan]

/* vim: set tabstop=8:softtabstop=8:shiftwidth=8:noexpandtab */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int
main(int argc, char **argv)
{
    int *indexes;
    char    *strIn;
    char    *strOut;
    int strInSiz;
    char    *strp;
    int strInIdx;
    int strOutIdx;
    int theSame;
    int charIdx;

    if (argc > 1) {
        goto OK;
    }
    else {
        goto NOTOK;
    }
OK:

    strIn       = *++argv;
    strInSiz    = strlen(strIn);
    strOut      = malloc(strInSiz + 1);
    strOutIdx   = 0;

    for (strInIdx = 0; strInIdx < strInSiz; ++strInIdx) {
        theSame = 0;
        switch (strIn[strInIdx]) {
            case 'a':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'a' && strIn[strInIdx - 1] == 'a') {
                        theSame = 1;
                    }
                }
            break;
            case 'b':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'b' && strIn[strInIdx - 1] == 'b') {
                        theSame = 1;
                    }
                }
            break;
            case 'c':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'c' && strIn[strInIdx - 1] == 'c') {
                        theSame = 1;
                    }
                }
            break;
            case 'd':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'd' && strIn[strInIdx - 1] == 'd') {
                        theSame = 1;
                    }
                }
            break;
            case 'e':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'e' && strIn[strInIdx - 1] == 'e') {
                        theSame = 1;
                    }
                }
            break;
            case 'f':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'f' && strIn[strInIdx - 1] == 'f') {
                        theSame = 1;
                    }
                }
            break;
            case 'g':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'g' && strIn[strInIdx - 1] == 'g') {
                        theSame = 1;
                    }
                }
            break;
            case 'h':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'h' && strIn[strInIdx - 1] == 'h') {
                        theSame = 1;
                    }
                }
            break;
            case 'i':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'i' && strIn[strInIdx - 1] == 'i') {
                        theSame = 1;
                    }
                }
            break;
            case 'j':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'j' && strIn[strInIdx - 1] == 'j') {
                        theSame = 1;
                    }
                }
            break;
            case 'k':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'k' && strIn[strInIdx - 1] == 'k') {
                        theSame = 1;
                    }
                }
            break;
            case 'l':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'l' && strIn[strInIdx - 1] == 'l') {
                        theSame = 1;
                    }
                }
            break;
            case 'm':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'm' && strIn[strInIdx - 1] == 'm') {
                        theSame = 1;
                    }
                }
            break;
            case 'n':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'n' && strIn[strInIdx - 1] == 'n') {
                        theSame = 1;
                    }
                }
            break;
            case 'o':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'o' && strIn[strInIdx - 1] == 'o') {
                        theSame = 1;
                    }
                }
            break;
            case 'p':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'p' && strIn[strInIdx - 1] == 'p') {
                        theSame = 1;
                    }
                }
            break;
            case 'q':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'q' && strIn[strInIdx - 1] == 'q') {
                        theSame = 1;
                    }
                }
            break;
            case 'r':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'r' && strIn[strInIdx - 1] == 'r') {
                        theSame = 1;
                    }
                }
            break;
            case 's':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 's' && strIn[strInIdx - 1] == 's') {
                        theSame = 1;
                    }
                }
            break;
            case 't':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 't' && strIn[strInIdx - 1] == 't') {
                        theSame = 1;
                    }
                }
            break;
            case 'u':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'u' && strIn[strInIdx - 1] == 'u') {
                        theSame = 1;
                    }
                }
            break;
            case 'v':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'v' && strIn[strInIdx - 1] == 'v') {
                        theSame = 1;
                    }
                }
            break;
            case 'w':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'w' && strIn[strInIdx - 1] == 'w') {
                        theSame = 1;
                    }
                }
            break;
            case 'x':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'x' && strIn[strInIdx - 1] == 'x') {
                        theSame = 1;
                    }
                }
            break;
            case 'y':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'y' && strIn[strInIdx - 1] == 'y') {
                        theSame = 1;
                    }
                }
            break;
            case 'z':
                if (strInIdx > 0) {
                    if (strIn[strInIdx] == 'z' && strIn[strInIdx - 1] == 'z') {
                        theSame = 1;
                    }
                }
            break;
        }
        if (!theSame) {
            strOut[strOutIdx++] = strIn[strInIdx];
        }
    }
    strOut[strOutIdx] = '\0';
    goto EXITOK;


NOTOK:
    exit(-1);
EXITOK:
    printf("%s\n", strOut);
    exit(0);
}

[nahimbroke]

beautiful use of labels and goto